When Atari undertook the design of the game, they expected wild commercial success. The whirlwind development process was designed to capitalize on the incredible popularity of Steven Spielberg's movie. Unfortunately, it also lead to an extremely poor level of quality in the final game, which was boring, confusing, and featured abominable graphics:

The result was millions of unsold cartridges that the company had no way to dispose of. Eventually, the hit on the solution of burying the cartridges in a dump outside of Alamogordo, New Mexico.

I first heard of the dumping from Nick Montfort's excellent history of the Atari 2600, Racing the Beam. For more on the topic, see the Wikipedia and Snopes articles on the topic.

This 3D modeling project is the first step towards building a diorama depicting the full dump with millions of cartridges, the concrete slab that covers it, and the New Mexico dessert and sunset above.

To start out, I searched out high quality scans of the Atari cartridge online. I ended up finding them on Atari Age. Here, for example, is the front of the cartridge:

I used these high resolution scans and some other research to figure out the dimensions of the cartridge and set about building a basic rectangular solid that matched these dimensions.

I used Blender as my 3D modeling tool of choice on the recommendation of Scott Wayne Indiana. With lots of help from Scott, I managed to get going with the basics in Blender and, eventually, I had a rectangular solid with the right proportions:

(Note, both Scott and I found Super3boy's Blender tutorials to be incredibly useful in the process of getting started with this complicated program. It's both humbling and really helpful to learn by listening to a bunch of tutorials narrated by a kid who sounds like he's about 7.)

After I had that down, I started working on adding the cutaways for the stickers on the top and front. Using Blender's "add difference marker" functionality, I was able to use separate rectangles to carve those out from the original slab. Then, finally, I added a bevel to the edge of the cartridge to simulate the roundness of the original:

Writing down this process in a few simple sentences makes it sound linear and straightforward. It was actually difficult and somewhat challenging. Without Scott's help, the entire endeavor would have taken significantly longer.

Once I had the basic shape of the cartridge worked out, it was time to try to add the graphic stickers to the top and side. After an initial attempt to navigate Blender's nest of menus (aided by this tutorial on textures in Blender) I eventually managed to map the image all over my entire object:

This was not quite what I wanted, but it was exciting to see an image actually appear for the first time. Eventually, I found the Blender wiki tutorial on multiple materials which explained how I could apply an image to just one specific surface of my object. This also made the Blender menu system start to make sense to me for the first time (by explaining the way selections made in certain menus modified the options available to you in others.) The result was a cartridge that was really starting to look right:

The end cap should have the ET logo image on it — which isn't working for some reason I don't understand — but otherwise this is really starting to be what I was aiming for. I even added an additional gnarled black texture to emulate the molded plastic of the non-sticker part of the cartridge. I'll probably include that texture in the final print, but I'm not showing it here because it made it very hard to see the details of my 3D modeling in Blender's preview images.

There are two next steps forward for me on this project. One of them is to get a 3D print made of this cartridge, mainly to gain experience with 3D printing. The second step is to make a model of the ET box and start combining multiples of that box and this cartridge into the limitless pile that sits under the Alamogordo sand.

Way back during orientation week, a few of us were talking about music, as you do when you're just getting to know a new group of people. Specifically, Marko Manriquez and I shared our enthusiasm for Aphex Twin. We talked about the incredible variation and detail that shows up in the drum programming in pieces such as Girl/Boy Song and wondered whether such intricately constructed music could possibly have just been made by hand or whether some kind of algorithm helped out.

I speculated that you could accomplish something like that style of non-repeating linear invention by using probability. You would just declare a set of allowed pitches and metric values to be assigned to each instrument and then allow the computer to randomly choose between those over-and-over to compose the piece. That would allow you to shape the aesthetics of the output without having to go in and make all the tiny micro decisions required to through-compose something with as much mind-boggling detail as the drums in Girl/Boy Song. (For the record, I don't believe that this is actually how Aphex Twin works; I think he actually writes all of that stuff by hand.)

Having had this idea, I sat down during the Tisch Convocation and wrote Whoops, a Ruby library that uses probability to generate scores for bloopsaphone, _why the lucky stiff's 8-bit music generator. Bloopsaphone uses a very simple text-based score system where, for exaple, "4C" would mean "play a quarter note on C", etc., which made it very easy to implement this idea in an environment where I could get instant feedback in the form of listenable music.

This was all back in late August of last year. I haven't touched Whoops since.

So, yesterday, for 4-in-4 I decided to actually use Whoops to create a piece of music. I started by defining a bunch of bloopsaphone sounds: hi-hat, snare, bass drum, lead melody, and bass. Next, I started using Whoops to define what I wanted the drums to do.

If you look at lines 53-57 of that ruby script, you can see the Whoops commands that generated the drums. I'm always having them play C since they're a percussive instrument anyway and their pitch doesn't matter. For the bass drum and hi-hat, I mostly want quarter notes (this is Aphex-inspired IDM, after all) so I give "4" as the most common value in the duration array. I want the snare to feel like it's largely on the 2 and 4 so I mostly give it half notes in its duration array. And then, I added one more sequence for the hi-hat, "hat_detail", that plays spastically on small duration increments (16,32, and even 18 and 9 for 16th and 8th note triplets). I gave that sequence mostly rests (the empty string) as its pitches so that it would only play occasionally; I wanted it to be decorative, not totally take over.

Once I had the drums starting to sound how I wanted, I figured out a chord progression for the melody and bass to follow and wrote down sets of notes that they should be playing for each chord. Then, I followed the bloopsaphone API to play the resulting music and also made sure that my script would spit out the actual notes generated for each instrument. That way, each time I ran the script, I'd get a different musical result and if I liked one, I could copy and paste the score for it so I could reproduce it and even modify and improve it if I wanted to.

After lots of runs, I had a few versions of things that I liked. The melody was the weakest. Some runs would have bits of compelling melody in the patterns that happened to come out but it was rare also not to have bits of weird dissonance or just melodic incoherence. So, I went in and edited the melodies I liked best to tweak them into a more compelling shape through classic melodic rules such as repeating patterns that were already there or adding sequence and series. The results sounded like this, for example: whoops_demo_2.mp3.

Here's the score for that fragment:

Once I had a couple of bits that I liked, I outputted the instruments one at a time to AIFFs using Soundflower and GarageBand and then brought the resulting files into Logic to mix. I was surprised at how easy and fun it was to mix these 8-bit sounds. I wasn't sure how well they'd take reverb, compression, and the other normal tools of music mixing, but I ended up pretty happy with the sounds that I got.

I didn't have time to put together a long-scale composition, but I did finish a sketch for a song. I'm calling it "And He Built A Crooked House". Listen to it here: And He Built A Crooked House.

The museum's proprietor, Fred Bobrow, is an enthusiastic guide to this literature, willing to talk endlessly about all the tricks the games' designers pulled to achieve their effects. He even opened up a few of the cabinets so we could see how they worked, revealing an amazing universe of magician-caliber optical trickery and incredibly intricate hand-built analog electronic systems.

For this post, I'll talk about a few of my favorite games and what I learned about how they worked (largely from Fred) and about the aesthetic qualities of their interactions (from playing them).

The first game I played on coming into the museum was Sega's Gun Fight.

This is a table top format game enclosed in a glass terrine. As you can see, it pits two cowboys together in a pistol duel across an tumbleweed-strewn western town. Each cowboy is positioned behind some cover consisting of a rock wall and two cactuses.

Each player stands behind his cowboy, with his hand on a gun-shaped control, and tries to shoot his opponent when he's visible through cover, without getting shot himself.

Players can move their cowboys from side to side along the slots beneath them. When you successfully hit another player, their cowboy collapses for a few seconds and your score is increased:

(If you shoot a cactus, it will fall over as well.)

Fred explained that beneath the surface of the machine is a series of lines of contacts. When both cowboys are lined up on the same contact line and one of them presses the trigger, that closes a circuit engaging the solenoid that adds slack to the rubber bands keeping the opposing cowboy standing up (so that the falls down) and causes the next bulb in the score display to light up.

Many games throughout the arcade used this technique of having a series of conductive lines on a circuit board closing a circuit between moving players and targets determine hit accuracy.

The next game I played was Chicago Coin's Motorcycle:

This game's main attraction is its beautiful projected graphics. According to Fred, inside the cabinet are a series of three circular zoetrope style screens that spin at different rates to : one with the image for the background (produce the illusion of speed), one with the slower blue riders who appear on the inside of the track, and one with the faster yellow riders who appear on its outside.

These zoetropes all project their figures onto a translucent screen that's parallel to the floor inside the cabinet at about the height of the player's controls.

On top of that screen is another motorcycle figure, this one directly connected to the player's handlebar interface so that it moves side-to-side as the player steers. The final shadowbox image is then reflected by a 45 degree mirror so it can be seen by the player.

The game has a series of electrical contacts connected to the moving player motorcycle and the rotating non-player motorcycles. If any of these touch, a circuit is triggered representing a crash, causing flashing red lights and all of the rotation to stop. Also, there's another switch that detects each full revolution of the outer zoetrope which counts as the completion of a single lap. For each completed lap, the score counter on the top of the cabinet increases by one via a rotating number connected to a low RPM DC motor.

The player also has an acceleration control on his right handlebar. Turning that causes all of the zoetrope cylinders to spin faster.

The biggest problem with this game is that it is fiendishly difficult. Unless you barely touch the accelerator, the other motorcycles crash into you so quickly that you're constantly stopped, making for frustrating intermittent gameplay.

The quality and sophistication of the sound used in the games varies wildly from mechanical bells to simple square wave beeping to, surprisingly, pre-recorded sounds.

A great example of the latter is Bally Space Flight:

If you listen carefully over the sound of other games and Hey Jude on the arcade stereo, you can here a series of radio transmission from mission control to the pilot of this lunar lander. These sounds are, amazingly, played via 8-track tapes which are kept in synch with the rest of the gameplay via high pitched noises outside the range of human hearing that are included on the tracks and which are picked up by simple microphones in the analog circuitry controlling the game. The tapes include these sounds every 18 seconds so that the circuitry controlling the downward movement of your space shuttle won't wander out of phase with the voice of mission control.

Then, the sensors in the game which detect whether you've successfully gotten your shuttle's glowing red landing pod into the hole in each crater, trigger different tapes to play based on whether mission control should be congratulating or haranguing you with "abort" warnings.

One very common technique in these games is the use of beam splitting one-way mirrors to superimpose figures on a scene and to enhance the illusion of depth in the space portrayed inside the relatively small cabinets.

A great example of using mirrors to superimpose moving figures on a static background is Commando:

While it looks like this seascape diorama is located directly in front of you while you're playing the game, it is, in fact, hidden in a compartment in the body of the cabinet and rotated 90 degrees to the vertical. You see it reflected in a one-way mirror placed at a 45 degree angle in front of you. This setup allows the scene to have more depth than would be possible in the standard 20 inch deep cabinet.

The flying helicopters moving across this landscape are located in the compartment of the cabinet directly in front of the player. They're lit with black light so that they'll shine through the one-way mirror without making anything else back there visible.

Part of the purpose of this surprising, but apparently quite common design was to keep cabinets at a size that would allow them to fit through standard doorways while still providing players with a game world that had more than 20 or so inches of depth. Since the games needed to be head and shoulder height anyway, why not take advantage of the optical path created by the long cabinet to enhance the illusion of depth.

Fred explained this principle to us by showing us the insides of Shoot Out, another Western-themed game that takes advantage of this optical path trick to portray a long and dusty western street.

Fred unlocked the bottom of the cabinet and opened the door to show us the saloon at the end of the street upside down in the bottom of the cabinet, facing up towards the one-way mirror.

He then had us look into the main area of the screen while he stuck his hand into the bottom diorama — lo and behold, his fingers descended from the sky of the western street to dance along the top of the saloon!

One of the highlights of the trip for me was when Fred opened up the bottom of Chicago Coin's World Series baseball game to show me the nest of relays, wires, discs, and other mechanisms that make the game go. First, so you can appreciate what's being achieved, here's a picture of the game itself:

Now, take a look inside:

Here, Fred is pointing out the relay that chooses which type of pitch will be thrown: slider, fastball, or curve. Its settings are controlled by this interface on the top of the game:

The bank of relays and switches on the right of that picture above gets used in resetting the entire state of the game including the number of pitches available to the player and the score.

Here's a picture of the amazing, early circuit board that serves as the brains of the operation:

Overall, it was an amazing trip and I can't wait to schedule an appointment to go back and have Fred show me all of the workings of the various games.

The incredible beauty and diversity of the visual and other effects these games with such simple mechanical and electrical systems is deeply inspiring and the actual details of the tricks they use could be a great reference for aspiring physical computing interface designers.

I put a ton more photos and videos in my Retro Arcade Museum set on Flickr. So take a look there if you want to see more. And if you get a chance to drop by the museum, don't miss it. It's a truly amazing place.

There are many types of randomness, but for my money they can be divided into two broad categories, which I'll call 'stochastic' and 'orthogonally causal'.

By stochastic randomness, I mean to indicate the traditional connotation of randomness used in the sciences: a condition where a system's future state is not derivable from its current state. In other words, in a stochastic system, there is some element that is non-determinative, that can't be predicted even with a perfect understanding of the forces at work, for example quantum indeterminacy.

The second form of randomness is more modest, but also a bit harder to explain. By 'orthogonally causal' randomness I mean the use of data that is unrelated to a given situation in order to produce information or behavior that seems random within the context of the given situation. In other words, even though the unrelated data may be determinative within its own context, its determining rule is completely alien to the context in which it's being used and hence it appears non-determinative. This form of randomness is preferred in many practical applications where generating hard-to-predict data can be useful; for example, many computer programs use the current time in seconds or some other piece of arbitrary data as a random seed when generating passwords or suprising behavior in game AIs.

This week, Jason Aston and I set out to build a piece for Living Art that embodied orthogonally causal randomness: a basketball-shooting robot that aimed based on the price of the stock market.

Within the system of aiming and shooting a basketball, the price of the stock market — structured and patterned though it, arguably, may be — appears highly non-deterministic. The spatial relationship between the shooting arm and the basket is almost completely orthogonal to the changes in the DOW, hence aiming based on that metric will appear highly random.

Aesthetically, we liked this combination for a number of reasons. Firstly, it combined two cliched signs of hyper-masculinity: high-powered finance and competitive sports. Secondly, the outcome (a small robot arm repeatedly failing to shoot a ball into a miniature hoop and, in the process, hurling balls all over the place) had a certain pathetic quality that seemed to resonate with the sorry state of the international financial system the last few years.

A video showing the evolution and final form of the bot:

A Random Project: Hoop Dreams with Wall Street Vim from Jason Aston on Vimeo.

As you can see in the video, we started designing the project by experimenting with a rotary solenoid. We hooked the solenoid up to a bench supply and tweaked the voltage until we started seeing it snap back and forth vigorously. For our model, that turned out to be about 25 volts.

Next, we worked on prototyping a ball-loading mechanism that would allow the repeating motion of the solenoid to fire off a series of miniature basketballs. That's the wood-paneled box the arm is thwacking early on in the video:

After some experiments, we settled on a design that used a hinged door and a single spring to restrain the balls while still allowing the arm to pull them out. Finding a spring with just the right force and placing it far enough back on the lid that it would simultaneously hold the balls in, not be too hard for the arm to pull-down, but not allow too many balls out with each throw was a challenge.

Once we'd gotten a prototype that we thought would work, we went over to K-Mart to shop for balls. We ended up settling on ping pong balls. Even though the don't look like basketballs, they were light enough and about the right size for our arm.

We brought the balls back to the shop and proceeded to rebuild the loading mechanism to the appropriate dimensions for the ping pong balls. We also mounted it and the throwing arm on a stand so that their relative position would be just right for getting a consistent launch.

As you can see in this picture, we left the throwing arm on a hinge so we could make small adjustments to its angle. After many experiments with it, we ended up concluding that we actually needed to tip the arm and loader back at an angle to get the balls to fly out at a basketball shot-like angle and to reduce the frequency of multiple firings that could result from two balls slipping out when the arm pulled down the trap door.

You can also see, in that picture, the basketball hoop we built. We looked at some pictures online and then Jason sanded a piece of balsa wood into the shape of the backboard. We built the rim out of a piece of red-shielded solid core wire that we soldered to itself. The cutting board base gave a nice court texture to the piece.

Once we'd gotten this shooting mechanism down, we had to work on the aiming. We used the H-Bridge lab instructions and the Arduino Stepper library to connect up a Nema 17 from Makerbot. We did the basic stepper hello world of getting the motor moving back and forth in both directions and then proceeded to work on getting in the stock market data.

To accomplish this, I transcribed the weekly closes of the Dow Jones Industrial Average over the all of 2008 and 2009 from Google Finance. Then, I manipulated the data a bit with Ruby to generate an array containing the price changes from week to week during that period. We copied and pasted this into our Arduino sketch, did some mapping so that drops in the market would correspond to proportional counterclockwise moves and rises to clockwise ones. Before we knew it, the stepper was spinning back and forth with the rising and falling (mostly falling) fortunes of the market.

Finally, all that remained was mounting the throwing arm and ball loader on top of the stepper. This turned out to be slightly trickier than we imagined.

First we tried using a lazy susan ball bearing. The idea was to remove the burden of actually holding up the weight of the arm platform from the stepper so that it only had to put force into rotating things. We mounted a wooden piece on one half of the bearing and attached a shaft collar that we'd drilled out to fit the stepper:

This let us mate the stepper to the top half of the bearing and still have the bottom half free to mount on a base. Jason then cut a square hole out of a piece of wood to restrain the stepper so that its rotation would be fully transfered into the assemblage above.

However, when we got the whole thing mounted in place, we found that the two sides of our box weren't precisely even and so the bottom bearing surface wasn't exactly perpendicular to the stepper's shaft. The result was that as the stepper tried to turn to one side, tension would increase dramatically and it wouldn't be able to continue. This effect far outweighed the benefits of relieving the weight so we removed the lazy susan bearing and mounted the arm platform onto the shaft directly, using the restraining mounting we'd built as a seat to channel the weight directly through the motor into the box as a whole:

Even though things weren't perfect and the motor would wobble and make minor complaining sounds, the setup worked well enough and we decided to finish up. We closed up the box around the circuit so that the hoop could sit at the same level as the shooting arm and the ugly electronics would be less visible:

Finally, at the very last minute, we experimented with trying to add a display screen in Processing that would show the percentage change to the stock market each week in sync with the arm's moves and shots:

The idea was to hint at the stock market-derived nature of the aiming data without actually declaring it directly. As if the percentage change was some kind of metric the machine was using (very poorly) to try to correct its own aim. Unfortunately, we didn't have time to get this piece of the project working before the demo (trying to integrate a serial handshake in 10 minutes at 9am just before presenting isn't the greatest idea).

As you can see in the video above, the actual performance of the machine in class was a blur of flying ping pong balls that sent our classmates to giggling and scurrying around the room.

The best feedback we received in the critique was that the we should work on the timing of the turn, aim, fire loop more in order to bring out more of the personality of the machine. In other words, if it turned, waited deliberately (as if carefully lining up its shot), then fired, then waited again (as if watching the result with interest), and then turned, etc. it would be much easier for people to project intention and other human qualities onto it which would make the drama of it missing so badly more effective.

Another interesting point, with which I'm not sure I agree, was that people wanted to see it using real time stock market data.

They also wanted us to build a more human looking arm around the throwing arm, something we intended to do, but simply ran out of time for with the engineering challenges around mounting the stepper.

Jason and I are going to continue to work on this project some in the coming weeks, hopefully sorting out some of the mechanical problems with the stepper and making the whole thing more aesthetically attractive.

Approaching it in this reluctant spirit, I was surprised to find Lanier's text not only far superior to the usual example of this genre, but deeply resonant with my own disappointments with web culture in the last decade or so.

Lanier draws a connection between the core design decisions of Web 2.0 and what he calls "cybernetic totalists" — Singularity-enthusiasts, semantic web-ists, and others who believe that the internet itself is becoming alive or sentient in some way. From Wikipedia to Digg to YouTube, many Web 2.0 designs de-emphasize the specific personalities of their individual contributors in order to create the impression that their content arose organically as an almost accidental side-effect of the artificial intelligence embodied in the site's architecture.

Lanier sees this as an attempt to make the prophecy of the Singularity seem more accurate than it in fact is. If the writing or editing or videography of real people is reduced to 'User Generated Content', the mere raw material from which something of value is made via algorithm, then machine intelligence seems both more sophisticated and more valuable than may actually be the case.

His most vivid stating of this case comes in the form of a surprising interpretation of the famous Turing Test. Conventionally, the Turing Test is a landmark for AI: if a computer program can successfully pose as human in a text-only exchange then it has achieved some landmark on the road to intelligence. However, Lanier argues, when a person mistakes a program for a fellow human being that is not the sign of the success of the machine, but of the failure of the person. The computer hasn't achieved humanity, we have lost, or intentionally forfeited or reduced, some part of ours. Machines don't pass the Turing Test, people fail it.

For Lanier, this is what happens when we try to see human-calibre intelligence in the behavior of search engines, collaborative editing schemes, or user voting systems. We define intelligence down. We forget the genius involved in the real set of actions and decisions made by the people whose actions are aggregated in order to praise the mere mechanical aggregator. It's a classic example of the pathetic fallacy

Another related thrust of Lanier's argument that I find highly compelling has to do with the role of anonymity in "open culture".

As a musician, Lanier tells us, he would be glad to apply a permissive license to his own work from a commercial point-of-view, but he wants to maintain a deeper form of personal connection than is made possible by anonymous reuse.

Why not have a flavor of Creative Commons license, he proposes, that would require a potential reuser to contact him in order to explain the proposed reuse? He wouldn't have a veto right over the reuser, but simply a right of notification, a chance for interaction, for conversation.

As a musician (and programmer and animator and photographer) myself, I find this suggestion delightful. I have little interest in making a living from the media I create, but have found great joy in the relationships I have formed through its reception.

The only reason to abhor such a suggestion, to insist on the power of anonymous fluid reuse is to create the illusion of a gap between the products of open culture and its authors. It's through this exact gap that the pathetic fallacy of machine intelligence grows. If we can't see the authors of all this open culture, it must be a product of the system itself.

Despite the power of Lanier's assault on Singularity Thinking, to my mind, he flounders terribly when he turns his argument towards aesthetic evidence.

Lanier proposes that over the last 20 years, with the rise of digital creation and networked distribution, musical creativity has faltered, falling into a retro phase of merely mashing up the past rather than generating the radically fresh sounds and ideas we might expect to have arisen from the introduction of such a powerful set of new tools.

Why isn't pop music substantially different than it was at the start of the digital age? Where's the new music that's as different from hip-hop as hip-hop was from The Beatles?

I find this idea to be extremely wrong-headed for three primary reasons. First, there are strong examples of music that could not, on a purely technical basis, even have been made before the digital era. Second, much of the best new music stems from a depth and breadth of musical literacy that would be unattainable without the incredible variety of material available in the contemporary digital music catalog. Finally, and most importantly, digital culture has fragmented the formerly monolithic structure of musical taste, hollowing out what was formerly known as "pop music" and returning music to the status of a folk art, i.e. one primarily produced and consumed locally for and by people themselves. Therefore, pop music is completely the wrong place to look for inventive music being made and consumed with passion.

The conversation about whether or not digital tools have resulted in new forms of musical expression since hip-hop need be no longer than two words: Aphex Twin. Take as exhibit one, Girl/Boy Song. Released in 1996 on the Richard D. James Album, Girl/Boy Song is built on a fundamental structure that would be inconceivable without digital composition tools: the intricate a-metric drum line as solo instrument. The song is introduced and anchored by synthesizer parts that are highly reminiscent of traditional classical music: they sound like strings and reed instruments, they play in rigorous counterpoint, etc. On top of this, however, is a wild whooping programmed percussion track that weaves between the beats, sometimes accenting it rhythmically, often spastically ignoring it, always with a level of micro-detail and variation that would be impossible for any human (or even embodied) performer to achieve. The song's aesthetic effect, the sense of stomach-dropping wonder, giddy acceleration, and sheer joy this music produces, comes directly from its digitally superhuman attributes.

In his quest for newness, Lanier describes playing contemporary music for young people and asking them to guess the decade in which it was written. Their inability to do this accurately, he argues, implies that the music of the last 20 years is all a rehash of earlier styles, retro stuff. I would like to see him try that experiment with Girl/Boy Song and other songs from the best work of Aphex Twin and a handful of other similar artists.

Lanier would certainly acknowledge, I'm sure, that digital culture has transformed music listening, dramatically increasing the variety of musical styles available to the average listener as well as the sheer number of recordings. A number of prominent artists today make work that is not specifically the product of digital creation tools, but would be inconceivable without the simultaneously broad-ranging and obsessively deep musical education made possible by these new digital archives.

For example take the Dirty Projectors. The Dirty Projectors combine guitar ideas derived from West African music with rhythms and vocal approaches extrapolated from hip-hop and soul and a compositional approach grown out of progressive 60s rock. For a canonical recent example, listen to Stillness Is The Move.

They are not, as a group similarly described in the 70s or 80s might have been, a "fusion" act. Fusion involved hanging world music tropes such as exotic instruments or pop sounds such as electric bass on the framework of modal jazz. It was noodley music for hippies and music geeks. The Dirty Projectors, on the other hand, are aggressively pop. Their beats are meant to move your body in an explicitly sexual way and their melodies are meant to get stuck in your head. They are doing the same thing The Beatles or Rolling Stones did, transmuting African-ate blues and Tin Pan Alley craft into liberatory music for young people, only with a much wider set of source material.

Another trend that bespeaks this expanded field of influence in contemporary music is the rise of what you might call post- or neo-classical artists. Here, I'm specifically thinking of harpist Joanna Newsom and violinist Owen Pallet. Both of these artists come from rigorous classical backgrounds and make music that addresses the aesthetic interests of classical music: orchestration, structure, development, virtuosity, subtlety, etc.

In an earlier era, Newsom and Pallet would almost definitely both have ended up as classical composers or performers. But since classical orchestras became museums dedicated to preserving the music of 19th Century Germany rather than performing today's composers, they found their outlet in the indie rock/youth music culture.

In the 80s, if you had told people that teens and twenty-somethings would line-up to see a wispy elfin woman play an hour-long song cycle on the harp filled with references to Samuel Barber and named after a mythical city in French Brittany they would have thought you were insane.

Finally, the fatal flaw to Lanier's analysis of contemporary pop music is the dissolution of "pop" itself. As centralized media was replaced with the decentralized net, a funny thing happened: pop music became less popular. Sure, many young people are still aware of its existence, but fewer and fewer use it to forge their identity. Young people still have powerful, emotionally formative experiences with music, but more and more of those are in relation to artists, and even genres, you've probably never heard of: Norwegian black metal, southern "crunk" hip-hop, Manchester trip-hop, etc. Music ties small social groups together, but is no longer a generation-uniting universal. Amongst people my age (30) and younger, I have little to no expectation that I'll ever have heard of a peer's favorite bands, let alone share them.

Pop music simply no longer posses the central generation-defining role that once made its vicissitudes seem like cultural sea changes. It doesn't matter in the way it once did. Beyond the net-enabled explosion of musical options described above, there are two additional reasons for this change.

First, as the music industry has shriveled economically, it has grown ever more entrenched in the tastes of the Baby Boomers. The Boomers outnumber real young people demographically, exceed their per capita music spending, and can be served by existing artists and catalogue. This trend is most obviously visible by the never-ending careers of artists like the Rolling Stones and Madonna, artists whose commercial presence lives on zombie-like long after their contribution to contemporary culture has ceased to be fresh. There's more and safer money to be made catering to Baby Boomer nostalgia than developing new acts that might excite the diverse tastes of the net generation.

Secondly, since digital tools have made it ridiculously cheap and easy to perform, record, and distribute music, a greater percentage of youth music appetite can be sated locally by small bands of their peers. Most of my favorite musicians are people I know. This isn't because of bias or because I'm especially well connected, but because music made in a community in which you participate ends up meaning more.

Another word for music like this — music made by local musicians to entertain their immediate peers — is "folk music". Most of the music I deeply love is folk music, not by style, but by mode of creation and distribution.

I hope that my defense of contemporary music is enough to convince Lanier (and anyone who thinks like him) of his error without letting the rest of you forget about the valuable ideas in the rest of You Are Not A Gadget.

The film contains striking footage of Petit 1768 feet about the ground, standing (or even more astoundingly, lying down) on a thin wire that seems, by turns, a solid surface and an invisible fantasy.

How does balancing work? The simplest recipe for balancing would go something like this: if you are off-center to the left, move your weight right; if you are off-center to the right, move your weight left. By using a Finite State Machine, you can make this recipe into instructions that can be executed by a machine. You can build a robot that tries to keep itself balanced.

This week, for Living Art, Allison Walker and I set out to do just that.

We started by hooking up an Adafruit 3-axis accelerometer breakout board to an Arduino and making sure we could read in the x-axis values. The breakout board needs 3v of power to use as a comparison with the values coming off of the accelerometer. At first we provided that with a simple Zener diode coming from the main Arduino 5v supply, but then (after losing that on the floor), we added an additional wire to hook up the accelerometer board to the Arduino's 3.3V supply directly.

Once we had the input coming in reliably, we used the Arduino Finite State Machine Library to connect the accelerometer input to a servo. The idea being that a servo connected to a long, wobbly leg could displace a balance beam in order to right itself when it began to get off center.

The Finite State Machine code we wrote (see the final source at the bottom of this post) ended up very straightforward. We had two states: LeaningLeft and LeaningRight. And two transitions between them: correctLeftLean and correctRightLean.

Once we had the servo reacting relatively correctly to the motion of the accelerometer, we rubber-banded the whole assemblage together. Allison built a leg for it to stand on and affixed that leg to a round wooden shaft so that the bot could roll over left or right but not tip over forward or backwards (along which axes it had no ability to correct itself).

Finally, we attached a balance beam to the bots' servo and set it loose.

We quickly discovered that the balance beam was nowhere near heavy enough or long enough to actually give the bot a chance of keeping itself vertical. Additionally, while the feedback between the accelerometer and the servo moved the beam in basically the right direction as we tilted the bot around, it's central point never seemed completely correct and it was prone to overreaction. Finally, the bot's leg was probably far too long meaning that as soon as the bot was slightly off axis, the rotational force would build up rapidly, throwing it straight to the table.

During our in-class critique, our fellow students had helpful ideas like examining how Victorian-era balancing toys use counterweights

and actually taking tightrope-walking lessons at the Chelsea Pier.

I intend to keep working on this project. The image of a tiny balancing bot, re-enacting Petit's "coup" at the top of a miniature replica of the now-vanished towers sticks with me.

Regardless, sometime recently, this blog turned five years old.

I decided to tell the story of a simple wine key. Like everyone else, I can't help but see a human form every time I look at one of these guys. With its extended arm, upturned eager face, monopod leg, and arm-like motion the temptation to personify these is so strong, I'm surprised I've never seen one as an animated character before.

Once I had the idea of animating a wine key, I started thinking about the world a wine key might inhabit, its hopes and dreams. The storyboard I ended up with tells the tale of a wine key's epic journey out of the drawer onto the counter in order to fulfill its lifelong dream of opening a bottle.

Here's an animated GIF that will show you the storyboard in five second frames (may take a little while to load, it's a 1.5mb file).

For something I'm supposed to animate in a week, this story ended up a bit.. .complex. Hence, this week I'm working on exploring just the basics of bringing the wine key to life: how it will move around, how it will express emotion, how it will interact with a few objects in its surroundings.

I'll post the final animation this week when it's done. Wish me luck!

Note: all the 'balancing' between the players and the warden in this game has been tuned for games with four prisoners as that's all we have available. Certain numbers such as nights of work needed to escape and points needed for parole points may need to be tweaked for larger groups.

Players

• 1 Warden
• 4-? Prisoners

Objectives

The prisoners have two ways to win:

1. 1) Breaking out of prison
2. 2) Getting paroled

The warden has two ways to win:

1. 1) Parole a prisoner
2. 2) Catch all the prisoners working before they escape

To break out of prison, the prisoners, as a group, must complete (6) nights of work on their escape. Each night, each prisoner has the chance to work on the escape or not. For each prisoner who works without getting caught, one night's work is completed.

If all (6) nights of work are completed, all surviving prisoners win and the game is over.

In order to get paroled, a prisoner needs to receive 3 parole tokens from the warden. The warden can give these out each round in exchange for information about who's working.

If a single prisoner is paroled, the game ends, that prisoner wins and the warden also wins.

The warden also wins if all the prisoners have been caught working without any of them getting paroled.

Playing

Each day, while the warden is sequestered in his office, the prisoners formulate a plan. They decide who will work and those who will place a work token secretly in front of them.

Once they have decided who is working and who is not, each prisoner, one-by-one, goes to visit the warden for a private conversation. If the prisoner and the warden come to an agreement, the prisoner gives the warden information in exchange for a parole token. If the prisoner does not agree to accept the parole token, no information is exchanged.

The warden can only give out one parole token per day. If any prisoner receives (3) parole tokens, then that prisoner is paroled and wins the game. The warden also wins.

Once the warden has visited with all the prisoners, the warden returns to the yard and chooses which prisoner's cell to search. It the chosen prisoner is working that night, he is caught and out of the game. If not, he is safe and remains in the game.

With the warden's back turned, the prisoners who successfully worked now place their work tokens in public. If they have greater than (6), the remaining prisoners escape and the game is over.

If the prisoners have not yet escaped, they get a chance to investigate each other for collaboration with the warden. At the start of the game, each prisoner is issued a shiv. At this point in play, any prisoner with a shiv can accuse one of his fellows of collaborating with the warden. If the accused has received any parole tokens from the warden, he is shived and out of the game. Otherwise, if he has none, the accused takes possession of the accuser's shiv.

If the prisoners have not yet escaped and no one has been paroled, the day ends and the next day begins.

Thanks, Morgen for uploading.

It was interesting to try to explain version control from scratch to a relatively less technical audience. I've taught git before to teams of developers who were already used to using Subversion in their daily work. This group ranged from people who had never even heard of version control to people who were comfortable with SVN and were mostly curious to learn about Git and GitHub, specifically.

I tried to be relatively straightforward about the differences between centralized and decentralized models, but I'm afraid my bias may have come through a little bit.

Anyway, in case it's useful to anyone else, I'm embedding the slides below. And, of course, the keynote and my notes are available on GitHub.

A silly, but compelling, example is 241543903:

Google Image search results for "241543903" shows exactly how effective this set of simple rules has been at generating a lot of interesting activity.

Morgen and I decided to team up to see if we could create rules that would use music to explore a physical space. The idea was to use logic about where the performers are located in the room to differentiate them into different sound-making roles so that the resulting music would change based on the specifics of where it was performed. To accomplish this, we had to figure out a way to use a single set of instructions to differentiate the performers from each other based on their position in the room. To do this we came up with a series of if statements based on spatial position. The idea was that it might be complicated and confusing to read through the piece the first time, but once you'd identified which rule applied to you, actually performing your part would be relatively straightforward.

We also tried to give the piece some dramatic shape, to design something that would have a beginning, middle, and end. To accomplish this, we came up with the idea of giving the performers phrases to play that would phase against each other — musical patterns that repeated at odd intervals so that they would only line up after a number of repetitions.

The result of all of this thinking was Instructions for Indoor Music:

If you are sitting closest to the door
  begin stomping your feet in an even pulse.

If you are the person closest to a corner
  clap on every stomp.
  
If the person next to you is in the corner
  clap on every other stomp.
  
If you are more than two people away from any corner
  say "ah" on every third stomp.

If you are exactly two people from a corner
  radically change the height of your head on every seventh stomp.

If you notice a stomp, clap, and "ah" happen simultaneously
  say "oh" on the next stomp.
  
If you hear "oh" three times
  stop everything.

In the process of designing the piece, I put together a demo of what it might sound like using bloopsaphone:

In that example, the low tonal sound is being used to represent someone standing up. This demo also indulges in the fantasy that all of the players would start together and stay together, an idea of which we were suspect even in the design phase.

On additional detail worth noting: we tried to exclude any expectations or requirements for the space or the people in it so that it would be applicable to (and malleable by) any possible space. That's why the only feature of the space we explicitly mention is the door and why we went for the awkwardly phrased instruction of "radically change the height of your head" instead of just staying "stand up" — so that the piece could be performed in a room without chairs (although I'm noticing now that we do refer to the "person sitting closest to the door" so maybe that's a bug that should be removed as well).

When class came, we put the instructions up on the screen and people started clapping and stomping. As expected, different people started at different times, with the person closest the door figuring their part out first and kicking things off. Unexpectedly, people didn't necessarily wait to understand the conclusion condition before starting and they also struggled mightily to both play their part and listen to others simultaneously. The result was a bit of a chaotic mess with some performers thinking they saw the stop condition and hence ceasing while others still continued. We even tried to perform the piece a second time after the rules had a chance to sink in and while those results were better the effect was still very little like a group of people playing music together.

I think the (interesting) failure of this idea came from a couple of factors. First, the complexity of the many rules was just too high for people to grok. Since their situation in space might have meant that multiple rules applied to them and since everyone had to listen for the conclusion condition (the last rule) on top of that, it was just cognitive overload for a lot of people. Second, the way we presented the rules — all at once on screen — probably worsened this problem, not giving people enough time to let each rule (and whether or not it applied to them) sink in.

Morgen shot some video of the performance and I'll post a link to that sometime soon when he's got it online.

In the aftermath of class, I started thinking about a radically simpler complement piece to follow up on what we learned from this first effort. As the piece evolved and we started thinking of it as "Instructions for Indoor Music", that naturally begged the question: What would 'Instructions for Outdoor Music' look like? Here's a piece that tries to learn from the failures of Instructions for Indoor Music while also answering that question. Instructions for Outdoor Music:

If no one is clapping
  begin clapping.

If more than one person is clapping
  stop clapping.

This week, for our first Methods of Motion assignment, I constructed five thaumatropes. Two of these used the two most common thaumatrope illusions: superimposing one image on another and combining two disparate images into a new whole. In the other three, however, I experimented with a different approach: using a thaumatrope to combine both sides of a stereograph in order to create a 3D effect. This second experiment met with mixed, but intriguing, results.

Finally, I built a lego prototype for a thaumatrope viewer. Normally, thaumatropes are viewed by rotating bits of twine attached to each end of the disk, causing it to spin end-over-end. However, this makes it hard to regulate the speed of the spin and forces you to change directions every few seconds as the twine uncoils. This viewer would allow you to play the thaumatrope by turning a hand crank in one continuous and comfortable motion, making it easier to control the speed of the spin and possible to play the thaumatrope without interruption.

First, my conventional thaumatropes. Since the thaumatrope illusion is created by having part of the image be absent on one side of the disk, I thought it would be appropriate to depict absence in the imagery I used as well. The first thing that came to mind on that theme was the Dodo.

Dodo Bird thaumatrope:

This thaumatrope combines a photograph of a dodo bird skeleton in a museum case with an artist's rendering of what the dodo might have looked like. When combined, the painted dodo bird appears to have real photographed bones visible inside of it.

One technical lesson from this thaumatrope: to my surprise, the white background of the living bird blocked out the darker surroundings of the museum photo. I was imagining that the living bird would simply be superimposed on the photograph, but the white background altered the effect. If I had given the bird a black background, the superimposition might have worked better, allowing the light details from the museum scene to come through.

In my second attempt, World Trade Center thaumatrope, I used this effect of the white background to my advantage. Another obvious image that comes to mind on the theme of "absence" is the World Trade Center.

In this thaumatrope, I took two copies of the iconic photograph of the WTC towers from below and erased one tower from each copy, replacing it with a white geometric gap where the tower was removed. The effect when the images are combined is of ghostly flickering towers, as if the towers were both present and absent.

Now, the stereothaumatropes.

I started out with a stereographic print that I found on the web depicting women working in a stereograph factory:

I carefully separated both sides of this image and aligned them in Photoshop to create a two-frame animation that would create the 3D illusion by oscillating rapidly between the two, a "wigglegram":

Once I'd gotten the images lined up, I split them apart again and flipped one, working very carefully to ensure the alignment would stay consistent when I printed them out and assembled them (like all the other thaumatropes here, I had this one printed at Adorama photo in NYC, which I can't recommend highly enough; they give you 25 free prints for opening a new account and made really good quality prints from my uploaded digital files overnight). Stereograph Factory Stereothaumatrope:

The 3D effect is not as pronounced in the thaumatrope as the wigglegram above — largely because the thaumatrope is actually spinning so fast that the image blurs — but it is visible. And the effect is even stronger in person.

I produced two more stereothaumatropes in this same manner, one of the Old Faithful geiser:

(view Old Faithful Stereothaumatrope on YouTube)

and one of this rocky mountain:

(view Rocky Mountain Stereothaumatrope on YouTube)

In this last stereothaumatrope, as you can see, I experimented with an oval shape as it fit the image better and I hoped it would slow down the spinning to enhance the 3d illusion. This worked maybe too well, making this thaumatrope actually somewhat too difficult to operate.

Which brings me back to the idea of a thaumatrope player.

A design for such a player faces two main challenges. First, mounting the thaumatropes securely without altering them. An effective player would be able to operate on existing thaumatropes without spearing them with a shaft or creating any new holes in them. After some thinking, I realized this means needing to clamp onto them from the bottom and spin them around left-to-right rather than top-to-bottom.

The second challenge, then, is converting from the vertical motion that is natural for the human arm into a horizontal rotation to spin the thaumatrope. After some sketching, I came up with a mechanism that would use two 45 degree gears mounted orthogonally to transfer the rotation. Here's a video of a Lego prototype that demonstrates the idea:

Prototype lego thaumatrope player

The biggest problem with this design is that the thaumatrope only rotates once for each revolution you make with your hand. To make it possible to achieve faster rotation, the gear ratio between the crank and the thaumatrope should be higher: making the thaumatrope rotate more than once for every turn of the crank.

Unfortunately, the Lego kit is somewhat limited in its gear selection, but I was able to slightly increase the ratio in a later prototype:

I intend to keep working on this thaumatrope player in my Mechanisms class with an eye towards eventually building it with real gears and lasercut parts.

The main advice that Greg Trefry (the prof teaching the class) gave us was: play your game; don't theorize or go off into flights of fancy about how we'd expect our users to act, but just get something simple working and play it repeatedly while refining the rules and mechanic.

So that's what we did. After an initial flurry of ideas, we dealt out one full deck to everyone in the group and started working on a game that involved placing cards face down and bluffing. With each round, we added rules, twiddled mechanics, changed procedures to prevent ambiguity, and added constraints.

The 15 minutes ended just as we put the finishing touches on the game and the class reconvened to play our game. At first, it was difficult to explain to the group of volunteer players exactly how things were supposed to work. We'd built-up the rules one at a time while playing so they weren't logically arranged in our minds for easy consumption. But once we got the group playing it, they seemed to enjoy it, laughing along as players got caught in bluffs and dynamics developed. The whole class even stuck around five minutes after its scheduled end to wait to see who would win.

It was a fun and fascinating introduction to game design. I can definitely see how this process would be addicting.

I've written up the rules of our game below. Please let me know if you try to play it.

Call Out, a game of doubt. For dice, cards, and 4 to 8 players.

The goal of Call Out is to use luck and your ability to bluff — and to tell when others are bluffing — to get get rid of all of your cards before any other players.

Deal out all the cards in the deck evenly to each player.

At the start of each round, one player rolls two six-sided dice, generating a number from 2 to 12. This is the Target Number. In turn, each player places on the table face down some of the cards in his hand. If the numerical value of the cards^[*] adds up to the Target Number this is a safe play. Otherwise, it is a bluff.

Once all the players have placed cards on the table, each player around the circle is given the option to Call Out other players: to accuse them of bluffing. If a caller correctly accuses another of bluffing, then the bluffer must take into his hand both his own face down cards and those of the caller. If the caller is incorrect, he must take both sets of cards.

Play proceeds in turn clockwise with each player still retaining cards in front of him having the option to either call a bluff or pass.

At the end of the round, the remaining bluffers place their cards in the discard pile; un-called players whose cards matched the Target Number (non-bluffers) return their cards to their hands.

The dice is rolled by the next player and the next round begins.

The game ends when one player runs out of cards. That player is the winner of the game.

^[*]Aces are worth 1, face cards, 10.

I began the ride uptown in the early stages of sunset. As I waited at the corner of Houston and Laguardia, night settled in around the buildings, chilling the sky's pale blue hue. Across the street, a brick four story's fire escape made intricate cuts in what was left of the light.

The M5 arrived. Hydraulics cranked beneath its undercarriage as the bus settled itself into position at the stop. It unfurled a small metallic suspension bridge towards the sidewalk, tonguelike. Two elderly chinese ladies descended this, emptying the bus.

"Do you know where the Film Forum is?"

The slightly less wrinkly of the two had squared off in front of me, almost standing on my shoes. After extensive repeating of street names and some strategic pointing, I managed to get them headed west down Houston, the right compass rose point at least and the best of the sunset between the buildings down that direction.

When I got off the bus at the top of its uptown route, disoriented, motion sick, and half asphyxiated, this turned out to have been one of only two moments of human conversation in the entire course of the journey.

I boarded the bus.

After retrieving my metro card from the automated payment machine and nodding to the driver, I took the inner windowside seat of a row halfway down the bus's length.

I looked up at the seat back in front of me and was suddenly transported across six months and three thousand miles. With the seat back hardware filling my field of vision, every visual cue told me I was back on the 15 commuting from Belmont into downtown Portland, as I'd done every morning the previous winter. With its cylindrical protuberances, circular bolts, and molded plastic back, the M5 seat resembled Portland's Tri-Met's in every detail. Anxiety rose within me mixed with a surprising sentimentality. I saw visions of a brick storefront office with bearded faces peering out from behind computer monitors and yellow anoraks; I felt the preparatory cringe as my body resisted passing through the threshold to start one more day of meaningless work, waiting.

When I came out of my revery, I discovered six other passengers had boarded with me. Three of the four singles sat in solo seats along the right side of the aisle. The frontmost of these, a small gray-haired lady with scars in her deep black skin, had surrounded herself with a small fortress of crinkly plastic shopping bags.

Up front, in a double seat, a woman spoke Chinese to a small boy with thick glasses.

A bald black man sat directly in front of me. His ears were doubly surrounded by slim-rimmed glasses and round white earbuds. His jacket collar protruded over the seat back making small synthetic whooshing noises as the bus jostled, revealing a gold-zippered hood and epaulets on the shoulders.

It was getting darker and we were already in the 20s, heading north on Avenue of the Americas.

We stopped and stopped. Passengers got on, blinking as they entered the humid glow of the bus's interior. Others got off, swallowed up by the increasingly impenetrable darkness outside. The seats filled up and some new arrivals began to stand in the aisle. The windows darkened enough to reflect internal light, sealing us off from the street.

A woman in the lead single seat fiddled with a cherry red cell phone, extending an old fashioned antenna nearly a foot from its top. Her face remained invisible behind a deep blue babushka with a printed metallic design. She focused intensely on the phone (was it a radio?) twiddling knobs and rhythmically leaning in close. The device's noise didn't carry across the growing crowd in the aisle.

Despite the fact that we were now alone — the group of us in this private glowing bubble gradually floating north — we were not, somehow, together. People acted as if they were in private, conducting intimate conversations loudly with neighboring friends in shared seats or distant ones invisible over the phone.

Near the front of the bus, a man with a white short-trimmed beard, a receding hairline and glasses held a varicolored New York street map with one hand while talking loudly into a phone cradled between his ear and shoulder: "You know when she was talking about that hotel the other day? When she was talking about that, she said, 'I'd live here.'"

We turned left on 59th to dodge around the park before continuing north on broadway.

A row behind me a gaunt effeminate teenager was complaining loudly to his female seat companion, one eye continuously on his cell: "Why did you take those things off your profile? I'm just asking. Am I still in your top friends? I'm just asking."

It was like an invisible gap had opened between us that both isolated and protected us from each other. People lost their fear of being overheard along with their ability to communicate.

I could stare at the backs of these people's heads intently enough to draw them and I could eavesdrop on their conversations clearly enough to transcribe them, but actually speaking to them or looking them directly in the eye would have violated the social contract of our little glowing cloistered world.

Just as this realization was settling over me, though, something happened.

We'd made our first stop on Riverside Drive, the inky blackness of the Hudson broken by gothic shadowy shapes of tree branches in the left bank of windows. I looked up from the sketch I'd been making of a beret-clad earbudded twenty something staring out into the dark to find that my seatmate had been watching me draw.

He jerked his eyes away when he saw I'd caught him, adjusting his posture towards the aisle. But then he turned back and looked up at me sheepishly. He was a middle aged black man in a Boston Red Sox windbreaker with the red knit cuffs rolled back to reveal a chunky silver watch. His hands were crossed over the newspaper in his lap.

"Great drawings there," he grinned. "Are you a student?"

"Thanks. Yeah. I'm heading up to Columbia to meet some friends." My cover story.

"Did you do one of me?"

"No. Not yet. I'm mostly doing the backs of peoples heads."

"I see. Ok. Well, good luck. This is me."

And he was gone up the aisle, squeezing his way between two asian girls giggling to each other, heads leaned in close, and off at the next stop into the dark.

I sat quietly for a few minutes as the river sped past outside the window. The bus made stops and gradually emptied out, leaving just a handful of passengers as we climbed north of 100th. The smell of exhaust started to fill the cabin and a swirling motion sickness took hold in my guts.

Despite this, I started to draw again: a Chinese man with a checkered fishing hat and gray tufts of hair at his temples. But this time something was different. The back of his head didn't feel like a barrier. The distance had closed. As I woozily filled in the geometric pattern covering his floppy hat, I started to imagine fragmented images from this man's life: hot afternoons on a glassy lake somewhere surrounded by smiling, round-faced grandchildren in overalls.

We rode further north, passing under an elevated train, beyond any part of Manhattan I'd ever seen. The smell of exhaust fumes worsened, my stomach swooned, and my head spun.

The bus stopped and stayed still for a long time, mechanical noises issuing from just outside, the hydraulic ramp again in action.

Finally, a wide motor-powered wheelchair made its way onto the bus. Its pilot wore a stocking over a baseball cap brim and most of his face, giving his head the appearance of a lumpy sock puppet. He wore a shapeless garment with wide vertical stripes that concealed his body's basic outline. There was a canvas bag slung over his wheelchair's head with the curved black grip of a cane poking out. Everything about his physical presence was armored and other.

With the driver's help, he maneuvered his wheelchair into position, taking the place of the side row of single seats that had been flipped up to make space. The bus pulled back out into traffic and I watched the back of his head for a few stops.

Around 160th, my wooziness overtook me and I desperately needed to be standing still in fresh air. I stumbled my way to the front of the bus, brushing past the man in the wheelchair — seeing a patch of dark skin and a flash of white eye through a hole in his ski mask — and then burst out into the street at the next stop, frantically filling my lungs.

I walked east down the first street I found, trying to clear my head and get my bearings. As the bus pulled away behind me, I was still trying to imagine it, the life beneath that mask.