Also found a circa 1939 K+E Favorite Slide Rule (4055). Looks like mahogany. It has A, B, C, D on front and S, L, T on back along with conversion tables.
It has 16 places in the lower register (8 places on the keyboard).
I multiplied 12,345,678 times 87,654,321 and the answer it cranked out is 1,082,152,022,374,638
My calculator?ÿ says 1.082152 x 10^15 which agrees but with lower precision.
Excel offers 1,082,152,022,374,640 - which appears to be due to a 15 place limit on output.
My longhand calculation agrees with the Monroe (638 in the rightmost places).
So this machine, which is built like the gears might have to move the Titanic, has more places than a modern computer :-D?ÿ Also note Monroe offered a model with 10 place keyboard and 20 place lower register.
Wow. Great Find. My dad used one for years. It burnt in his office fire. I've used it. When it starts making mistakes, clean the gears and working parts with Kerosene.
That is awesome. You know we put man on the moon with slide rules and those. Some of the most complex data was done with that technology and now i can??t get crews to pay attention to what height they measured lol.?ÿ
That's a great find Dave! I have the one my Dad used in the 50's - 60's. Using it may have been what piqued my curiosity in math, although the mechanics of it always fascinated me. He also had an electric model like hpalmer submitted, and I still remember the sounds it made.
My Dad had a Marchant Figurematic, wish I had it, don??t know what happened to it. He had it in the late 1960s then I visited his office around 1970 and the Marchant was replaced with an hp desktop calculator.
Wow. Great Find. My dad used one for years. It burnt in his office fire. I've used it. When it starts making mistakes, clean the gears and working parts with Kerosene.
Nate
I find that if I push through the resistence it produces correct answers.?ÿ If I go too fast the inertia makes the carriage jump so some of the gears don't turn correctly.?ÿ You are right, clean and lube and it'll work as good as new.?ÿ Possibly dates to the 1920s,?ÿ probably a model K.?ÿ The early model Ks have a four piece case, this one has a one piece case.?ÿ The mushroom style keys are the older style, the 1940s to 1960s models have cylindrical keys that hide the metal post and go down through a round hole.?ÿ On mine you can see the metal key posts with the mushroom key cap on top.
@hpalmer?ÿ I was still in high school when my boss, just a few years older than me, walked me through using a machine like that to angle and compass rule balance a 4 legged traverse that we ran around a block in Nyack, NY the day before. It was the coolest thing I had ever done.
