Kyle Rankin @kyle@librem.one

Subtraction was weird. You'd subtract w/ addition by the complements method, but would first subtract one from the number, then press down that number using the small digits on each key. You also slide the correct metal tab at the bottom to stop the carry. Here's 9 - 2.

You can perform many calculations surprisingly quickly and w/ one-hand. A well-trained Comptometer user was probably as fast as you'd get until electromechanical calculators. Here I'm calculating 1024 x 768, which just requires pressing 768 a few times and shifting left.

The Comptometer had a superior design. Pressing a key immediately updated the register, no need to pull a lever (the lever here clears the register). This design was so effective it stayed essentially the same (with minor improvements on error prevention) through the `50s.

This is a Comptometer Model E mechanical calculator, made between 1913 and 1914. Comptometers were made starting around 1900 and were a direct competitor to the 1908 Burroughs adding machine I featured earlier.

This is the carry mechanism for the Monroe. The bars form a wave and the last few move, but were completely seized up. A few hours with some oil, pliers, a screwdriver, and ultimately a heat gun, and it finally loosened up. Subtraction finally underflows all the way to the left!

Yesterday I spent a few hours restoring this Monroe Model G calculator. It was only after putting everything back together that I discovered the accumulator is only underflowing half the digits when doing subtraction/division, so I get to take it apart again today and fix that.

Of course if you can add repeatedly you can multiply, so this machine has a "repeat" button in the bottom right corner. Once pressed, any number you enter stays pressed down after you pull the addition lever, so you can add over and over just by pulling the lever.

The Burroughs is a true adding machine--it can only *add* numbers. Notice the limited buttons on the keyboard. If you ever heard someone refer to a modern calculator as an "adding machine" it derives from the fact that originally that's all they could do back in 1908.

This is my Burroughs Class 1, Model 7 Adder/Lister made in 1908. The glass sides and front let you watch the mechanisms as it's adding.

These antique calculators have a funny way of multiplying...

You may be laughing now, but after the zombie apocalypse wipes out the grid and you are calculating cryptocurrency with pencil and paper, I'll be laughing (and cranking) all the way to the (probably by then barter-based) bank!

New addition to the mechanical calculator collection! This Addometer by Reliable Typewriter and Adding Machine Co not only does basic arithmetic, the far right dial does simple fractions and the dial next to it that literally goes to eleven calculates by the dozen!

My wife said this represents the two of us, so I think I found the spot for my calculator.

Now that I fixed the register on my Monroe LN-160x, the overflow bell works which means I can perform division. Here I am calculating 145 / 12 = 12 remainder 1. The quotient is at the top in red, the remainder is underneath it in black.

Dinner is served. #bbq

Took my Monroe LN-160x apart for a little cleaning and to diagnose the stuck register in the leftmost column causing it to increment by 50000000 with every addition. A few drops of oil and some fidgeting and it loosened up. Now it's working great.

I (mostly) fixed my mechanical calculator! Here it is calculating 12 x 42. The 8th place from the right increments by 5 with each turn so I still need to take it apart and fix that but otherwise it is working well.

There's a new addition to my mechanical computer collection! This is a Monroe LN-160x mechanical calculator. I didn't notice at the time that it was missing the front lever for the carriage return, and it looks like I'll have to do some repair work to get it working again.

This double IPA is an opportunity to use up leftover hops from past beers. Here's the hop portions for the boil. There's another 180g besides this for dry hopping.

While I don't watch much anime, I'm a sucker for anything in a cyberpunk universe. I'm rewatching Ergo Proxy and this week's Apple Child Safety news reminded me of a concept in the show.

There are androids called "autoreivs" in this dystopian future. One type is called an Entourage and it is assigned to a particular human. They are a personal assistant and follow the person around, chauffeur, and even act as a bodyguard.