​The Antikythera mechanism

Recovered from a Greek shipwreck off the island of Antikythera, this small analog computer was designed to predict astronomical positions and eclipses, and it even tracked the cycle of the ancient Olympic Games.

The Antikythera mechanism is estimated to have been built around 205 BC, and its complexity went, as far as we know, unmatched until the invention of astronomical clocks in the 14th century.

​Napier's Bones

John Napier, a Scottish mathematician and physicist, invented this rod-based calculator in 1617. He based it on the lattice multiplication system that Ottoman mathematician Matraku00e7u0131 Nasuh popularized.

The bones are an amazing machine that can do addition, subtraction, multiplication, division, and even extract square roots. Unfortunately for Napier he died the very year he published his system, so he wasn’t around to see it enjoyed for very long.

​Pascaline

Blaise Pascal created his Pascaline calculator in 1642 when he was just 19 years old. He invented it for his father, who was a tax commissioner, because Pascal wished to reduce his workload. The Pascaline was the first in history to include a carrying mechanism, eliminating errors due to operators forgetting to carry the 1.

Pascal received royal privilege from the king of France for his design, making him the only one in the kingdom allowed to design and produce mechanical calculators. He tried commercializing the Pascaline but only sold about 20 of them in five years before getting bored with math and moving on to philosophy.

​Sector

Also known as the military calculator, the sector is just two rulers attached by a hinge. They are able to swing open and closed and feature several scales designed to do a bunch of different mathematical operations that most military officers at the time were unable to do.

The sector was likely a simultaneous invention of several mathematicians, but Galileo generally gets credit. The sector found wide use during its heyday since it was easy to produce and use. It found a home in architecture, gunnery, determining perspectives, surveying, and even music.

​Analytical engine

The first–and only–theoretical machine on the list, Charles Babbage’s analytical engine was never quite finished. It should work in theory, and if it were to be successfully constructed it would be the first Turing-complete computer in the history of the world.

The analytical engine was designed to allow for conditional branching and loops, have onboard memory, and be equipped with an arithmetic logic unit. It would use punch cards to input programs and store data (up to approximately 16 kB). Alas, Babbage and his chief engineer couldn’t stop arguing, so the British government pulled their funding in the late 1830s.

​Actinograph

Actinographs are the precursor to the modern light meter and were employed for the same purpose: to help photographers get better shots. Unlike their electronic counterparts, actinographs were more like a variation of the slide rule.

Slides were adjusted to account for plate speed, lense type, and other variables. The device was then placed against a card (or a roller) that tracked light through the course of the year so you could estimate just how long to expose film.

​Differential analyser

These machines were meant to solve–no surprise–differential equations. They did so by using integration calculated by a ball and disc system, which remained popular until it was replaced by electronic computers.

Differential analysers were first used to predict tides, and later for naval fire control systems. Machines not unlike the early 1872 model remained operational until the 1940s, when they were finally replaced with more practical–and powerful–computers.

​The Z1

The Z1 was the first computer in the world to use boolean logic and floating point numbers as the basis of its programming. It was, unfortunately, destroyed during bombing of Berlin in World War II, and its construction plans were lost as well.

Programs were punched into 35mm film, and the whole machine was built by its designer, Konrad Zuse, using thin metal sheets and a jigsaw. Zuse reconstructed the Z1 in 1986, recutting the nearly 20,000 parts by hand again.

​Lehmer sieve

In 1936, UC Berkeley professor Derrick Norman Lehmer enlisted his son to help him build a machine that could give them the remainders of two sets of numbers divided together. Called a sieve, their machine was initially constructed using bicycle chains.

The chains would spin, and as they did they would hit rods. Those rods in turn closed part of a circuit, and once the whole thing was closed the machine would have arrived at an answer. Not exactly practical, but neither is finding remainders from two massive number sets.

​Cryptography slide rule

The Aristo 90197 looks and operates just like a regular slide rule, but it doesn’t have anything written on it. That made it the perfect tool for cryptanalysts learning their trade: just write letters on it and slide it around to change the encryption.

The Aristo was commonly used to train cryptanalysts during World War II and the Cold War. Basic cryptographic functions like substitution and transposition were easy with the Aristo, making it an invaluable tool in protecting national secrets and sending coded messages.

​MONIAC

Fans of Terry Pratchett will likely recognize the MONIAC, but for those who haven’t read Making Money this one is straight out of the realm of fantasy. The MONIAC was designed in 1949 by an economist from New Zealand. It uses water that is pumped between chambers to simulate the economy of the United Kingdom.

Chambers had names like treasury, health, education, and most every other part of the economy. Water would be pumped from place to place, removed from the model to represent exports, added for imports, and moved around to simulate investment.

Pratchett’s fantasy version actually ends up spontaneously generating gold in the city treasury of Ankh Morpork, which as of this writing has yet to happen in any major financial center of our world.

​Chadwick Magic Brain

The Chadwick Magic Brain is a great example of a consumer calculating device from the era before electronics. It’s a purely mechanical device that uses a stylus to add, subtract, multiply, and divide.

The stylus would be placed in a slot next to the number the operator was working with, then slid up or down to add the number to the machine. It’s surprisingly simple to operate, and it was surprisingly cheap too: it cost $0.98 in 1962, which would make it a little less than $8.00 in 2016.

Curta

The Curta looks like one of two things: either a pepper mill or a piece of camera equipment. It doesn’t scream “calculator,” yet that’s exactly what it is. Numbers are input using slides on the side of the device, and a lever on the top is spun to add, subtract, multiply, and divide.

The designer, Curt Herzstark, actually finalized the design while being held in Buchenwald concentration camp during WWII. After the camp was liberated he found a factory to manufacture it, and the Curta later became one of the most popular mechanical calculators until the invention of electronic ones in the 1970s.

​KL-1

The KL-1 was a soviet design, and also the impetus for this gallery. It’s actually just a slide rule, but in a round form that is about the size of a pocketwatch. By sliding the face and a needle a user can multiply, divide, and perform a number of trigonometric functions.

I purchased one online, and it’s a really cool device. It’s tricky to use, but when I get a calculation correct it’s exciting. It also reminds of the alethiometer from The Golden Compass, which definitely isn’t the reason I bought it.