Kyle Rankin @kyle@librem.one

While it's hard to beat the aesthetic appeal of the Burroughs Class 1 and 3, they are big, heavy, and slow. If you don't need a paper record you'd be better served by its 1919 competitors the Comptometer Model F or Monroe Model G I featured here earlier.

Division is possible by repeated subtraction. Like with the Comptometer you have to watch the register before it underflows. To print a subtotal pull the lever once, hold the subtotal key and pull it again--a 2 handed operation. Total works the same but also clears the register.

You multiply by repeated addition in the ones column, then shift left and repeat for each digit in the multiplicand. Normally the keys reset when you pull the lever, but by pressing the repeat key they stay down until you press the Total key. Here is 12 x 12.

This is an adding machine--it only adds. To subtract, you have to use the complements method. For instance, to subtract 42 from 31342, I convert 42 to its complement (99999958) and add it. The carries shift off the left of the register and the difference remains.

To add, enter the first number in the keyboard and then pull the lever to add it to the register and print it on the tape. The enter the second number and pull the lever again. The lever provides the force necessary to print. Here's 31337 + 5.

The Class 3 is a rather different design from the Class 1. Like tech companies today, Burroughs expanded by buying competitors. This machine was originally made by the Pike company in 1909 which Burroughs bought in 1911 and it became a core part of a larger product line.

This is a Burroughs Class 3 adding machine from 1919. Where the Class 1 I featured here earlier has fancy beveled glass and a full carriage on the back to accept ledgers, this later Class 3 has a simple paper spool and was used for general accounting.

"It is manufactured by our "special process" which leaves the *individual molecules unscathed*, retaining the "rubber-ball" springiness of the oil."

@yaelwrites Sounds fun!

@yaelwrites I know that some folks only post about tech/security/etc on social media but avoiding cliques/echo chambers is one reason I post about my wide range of interests, including non-tech ones, and encourage other tech folks to do the same.

Whenever Apple says it's doing something for privacy or security, it's actually about control. It uses its control of hardware and software to beat its competition. https://www.ft.com/content/074b881f-a931-4986-888e-2ac53e286b9d?sharetype=blocked

@yaelwrites Nice! Here's one of mine. It was used to teach touch typing, that's why the keys are colorized:

https://social.librem.one/@kyle/106841485305774125

@yaelwrites Pics!

@yaelwrites There are of course a lot of them on sites like ebay too, but they are so heavy that shipping becomes expensive (and you risk damage) so it's often better to source locally.

@yaelwrites Some I found in antique stores or thrift stores, but the majority have been from individuals posting on craigslist who were getting rid of their (or their deceased spouse's) collection. There's some crossover from folks who collect vintage typewriters (I have a few of those too).

@yaelwrites I find them really fascinating. Most of them I've gotten so far aren't fully functional when I get them but I've found they are also pretty fun to work on and restore. Plus taking them apart means I can watch the machinery in action.

I plan to catalog them, print out placards and essentially have a small museum in my office.

@yaelwrites Check out my timeline on here to see my collection. I started collecting antique mechanical calculators in earnest earlier in the year and I've been featuring about one per week with descriptions and photos and videos of how they work. My current collection spans from about 1908 (Burroughs Class 1 Type 7) to the 1950s.

@yaelwrites I really liked the piece! Granted all of my favorite calculators are 80-100 years old and have gears and levers, so this is a bit fancy for me, but I'm definitely going to keep it in mind for when my son needs a calculator for school.