Review: Japanese Soroban Abacus

Let's say you go on a balloon ride around the world. Obviously you bring your calculator collection in case of emergency. Then an emergency happens. The balloon starts to rapidly lose altitude over the ocean. You grab the first calculator you get your hands on because there's no time to make a decision, and calculate that there's an island ahead. You land on the island safely, but the balloon is badly damaged and won't ever fly again.

Days pass, then weeks, and every calculator that uses batteries eventually stops working. But it's okay, because you also have your solar calculators. Well, it was okay until winter comes. See, you're in the Arctic circle, and nights can last more than twenty-four hours. Now you're going long periods of time with no access to an electronic calculator. Are you screwed?

The Japanese Soroban Abacus

Of course not! Because within your collection is the Japanese soroban abacus. It requires no electricity at all, and is just as effective as a calculator with basic functionality. I won't be one of those purists who claims an abacus is more effective than anything from Radio Shack, but it'll get the job done.

Even though it's built from wood with lots of open areas, the soroban is solid and sturdy. The beads slide smoothly over their individual dowels. Unfortunately, they slide a little too well, so this thing has to be operated on a flat surface for accuracy.

There's a plunger on the top left that resets the abacus. It never ceases to be satisfying, so I included a gif of this in action for you to enjoy.

I have no idea when this particular soroban was built or even what company made it. It's a beautiful device that I was excited to find at Goodwill for 99 cents.

Back of abacus, button not pressed.

Back of abacus, button pressed.

Review: Produx Original

I haven't said this for a few reviews, so it's time I say it again: thank you so much to everyone following these calculator reviews. I've loved the pictures and comments people have sent me. If you have a calculator you think is interesting, please send me a tweet or something. I'm also interested in any other vintage technology you'd like to share, so send me pictures of that stuff too. In the near future, I'd like to create a second blog specifically for old, forgotten technology, but calculators will remain my priority, of course.

Produx Original Calculator.

The Produx Original comes from West Germany some time between 1940 and 1960. This is just one of many mathematical devices from Produx, and since it doesn't seem like the company is around anymore, finding details is challenging.

Calling this device a machine is a stretch because the only moving parts are controlled entirely by using the stylus. I can't get inside the Produx Original without destroying it, but I can safely assume that there are no gears, levers, or mechanical mechanisms inside other than the sliding numerical parts.

So if everything's done manually, you'd think that means this is no less difficult than doing adding or subtracting by hand. And you'd be very wrong. With only a few minutes of practice, I was able to figure out how to quickly add and subtract large numbers without the aid of a manual or guide.

Green leather case for calculator and stylus.

The video review shows the process to perform operations, but it's little more than a matter of inputting an initial number, then inputting a second number that you want to add or subtract. For addition, you use the lower portion of the device, and for subtraction, use the upper. To clear the numbers back to zero, you simply pull up on the handle at the top of the calculator. There are a few tricks that might take a minute or so to learn, but overall the Produx Original is very intuitive.

Considering this device is over fifty years old, it's in fantastic condition. Even the leather case looks great. This is a calculator that was designed to last as it's made entirely of metal. It's definitely not cheap metal either because it's very difficult to bend (not that I tried that hard).

It's comfortable to hold and looks stunning. Despite it clearly looking like something decades old, there's hardly a scuff on the front of it. The previous owner(s) must have taken good care of this calculator and I hope they can rest easy knowing it's in good hands now.

I purchased this Produx on Ebay for $11.

Back of Produx Original.

Reset handle in use. Sets all values to 0.

Review: Golden Gem Automatic Adding Machine

Not every calculator I find is in great shape. Most of them require a bit of a cleanup before they're ready for review, but some are broken or severely damaged. It's extremely satisfying to bring a non-working device back to life, especially one that has been neglected for possibly decades.

Golden Gem Automatic Adding Machine

The Golden Gem Adding Machine came out in 1907. This particular model ended production in 1910, so it's fair to say that this device is well over a hundred years old. This is not only the oldest calculator I own, but probably the oldest thing I own. I found it in a local thrift store for $10 and the people working there had no idea what it was.

I wish I knew this calculator's story. I'd love to know what purpose it served when it was brand new, where it went from there, and how it ended up in that glass display a hundred years later. What I do know is that it hadn't been cared for in some time, as much of it was covered in rust and the reset function wasn't working properly.

Yet despite its age, despite its condition, it worked just fine. It's a simple device only capable of adding, but it uses a clever series of gears and chains to accomplish this.

If you wanted to add, say, 86 plus 49, you'd start by pulling the chain in the tens slot from the number eight, then do the same with the six in the ones slot. Then to add 49, you simply repeat the process but with four and then nine. This would display the result of 135.

How it works is simple. Whenever a digit is at 9 and 1 is added to it, the digit resets to zero, and the next digit up increases by 1. It is this simplicity that has allowed this device to survive for over a century. It's also the quality of its construction.

I use a Bic pencil for the stylus.

Holding it, the calculator is much heavier than it looks. If you shake it, you can hear the one loose chain rattling around, but it's clear that everything else inside is solidly constructed. Each pull of the chain is difficult because the gears inside have a lot to do, but simply just work. This calculator can handle the strength you put into it, and at no point does it ever feel like it's going to break. It's basically a solid block of iron.

In the near future I will post about cleaning and repairing this device.

Disassembled device

Top view, stand deployed.

Back view.