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Last night I got access to a digitized film reel from 1969 that shows off a computer artillery game called Potshot. And to explain why that’s a big deal, I need to talk about Dartmouth and the BASIC computer language.

In 1963-64, university faculty John Kemeny and Tom Kurtz developed the Dartmouth Time Sharing System, a time-share system notable for its speedy responses and accessibility for students and staff alike.

This was augmented further by their development of the BASIC computer language in 1964. That’s where a certain physics professor came in. Arthur Luehrmann saw the value of this system for education and entertainment early on, becoming an early evangelist for BASIC.

Luehrmann developed Potshot as an educational tool to show his physics students about gravity and velocity in an entertaining way. You can learn more through my interview with him from a few years ago: www.atariarchive.org/an-interview...

He developed two different versions of Potshot: a terrestrial one where players take turns shooting at each other over a mountain, and an orbital version that places the cannons in space.

The former was written up in People’s Computer Company in 1973, and that seems to have catalyzed the “artillery genre,” effectively making Potshot the progenitor! Games such as Artillery Duel, Scorched Earth, Gorillas.bas and Worms all trace their lineage back to Potshot.

While many DTSS programs still exist, as far as I know Potshot is lost. For decades we didn’t even know what it looked like beyond the PCC article. But Dartmouth’s library still features materials related to DTSS, including some film reels. I took a chance and reached out earlier this year.

I requested that one, Timeshared Computer Graphics, be digitized. I got the file a couple days ago and it surpassed my expectations, as it had a lengthy demonstration of both versions of Potshot!

We know now that Potshot didn’t use a standard teletype or a display monitor; Luehrmann explains in the film that the former was too slow and both too expensive to operate or own, respectively. Instead, it uses a plotter (or a storage display screen, a very specialized kind of monitor)!

Players input the parameters of the match on a teletype, and the plotter draws the landscape and the cannons. You then take turns firing at each other and the plotter draws out each shot, color coded for each player. Score a hit, and it even draws an explosion!

The orbital version is extremely fascinating to see as well, as it follows the actual physics of trying to hit another object in orbit; effectively you need to fire the opposite direction! To my knowledge no artillery game has ever tried to recreate this one as no one knew about it for decades.

Potshot itself may be gone, but between its description and this film, we know a lot about how it played, and its legacy. The film reel is under copyright so I haven’t figured out what to do with this snippet, but I may make a short video about Potshot and its legacy using it. Stay tuned!

As an addendum it sounds like the film may actually have fallen into the public domain under the 1976 copyright act, so hey, I may just be free and clear to throw it on YouTube this weekend

Thank you for such a comprehensive thread on this! Games played via Teletype are such a fascinating era of computer history.