Jaap Scherphuis

I just added to my site this manual for the Thales GEO double-register mechanical calculator, and uploaded a scan to archive .org. archive.org/details/thal... This was a special model with two input registers and two accumulator registers, attached to a single crank. I don't have this model, but...

I own a similar Brunsviga D 13Z/1. These were used for land surveying calculations. You can easily input the x,y components of a unit vector in the input (e.g. the sine/cosine of an angle from a lookup table), and multiply that by the length, adding it to the vector in the accumulator registers.

At today’s flea market I only saw this little Resulta E7, a small adding machine from Germany. This version is from the 1960s, though the first versions were made in the 1930s.

So here is the Locke Adder. A gorgeous looking thing which is really no more than an abacus. It does not even have a carry mechanism. I spent a lot of time looking through digital archives to find out more about it and the maker, Clarence Elmer Locke. I found a few things that seem to be new. 1/3

In May 1907 a fire destroyed Locke's business premises in Kensett, Iowa. It seems that he was unable or unwilling to rebuild his business, and the next year he moved to New Mexico to become a farmer. He died there in 1945. So production of the Adder probably ceased in 1907, not 1912 or 1916. (3/3)

So here is the Locke Adder. A gorgeous looking thing which is really no more than an abacus. It does not even have a carry mechanism. I spent a lot of time looking through digital archives to find out more about it and the maker, Clarence Elmer Locke. I found a few things that seem to be new. 1/3

On today’s visit to the fleamarkets I saw just one mechanical calculator, a good-looking Triumphator CRN2 pinwheel machine. These were made in Leipzig, East Germany, from about 1958 to about 1964.

Here is a video of the Add-O-Matic from 1947. I found out some new info from looking through online archives. Behind the sales company was the manufacturer United Enterprises Inc from Chicago. They made stainless steel cutlery, but also some other surprising things. (1/3) youtu.be/Uhhk94cbZ0A

By the way, the Add-O-Matic from Chicago (1947) should not be confused with the Add-O-Matic from Chicago (1937). They are completely unrelated adding machines. (3/3)

Here is a video of the Add-O-Matic from 1947. I found out some new info from looking through online archives. Behind the sales company was the manufacturer United Enterprises Inc from Chicago. They made stainless steel cutlery, but also some other surprising things. (1/3) youtu.be/Uhhk94cbZ0A

There was an inventor named William T Phillips who in 1917 developed an mechanical calculator. Just before he died in 1937, he wrote a biography of Butch Cassidy. Phillips had confided in friends that he had an outlaw past, and the unpublished manuscript had details that led some to believe ...(1/3)

... that he was actually Butch Cassidy. That somehow Cassidy had survived the shoot-out in Bolivia in 1909, moved to Spokane in 1911 and lived a nice quiet life there working in his machine shop. Eventually even Phillips's son, William R Phillips began to believe his father was Butch Cassidy. (2/3)

Here is a peek into how newspapers used to be made. I have a newspaper photo from about 1918, showing one Genevieve Deasy who was the world record holder on doing calculations on the Comptometer mechanical calculator. They inked the background black, and used white to accentuate some lines. (1/2)

Burroughs were always trying to one-up Felt and Tarrant, the makers of the Comptometer. Felt and Tarrant printed The Soldiers' French Phrase Book, giving it to soldiers for free. In the back is a Comptometer ad calling it the "Rapid-Fire Adding Machine", and the "Machine Gun of the Office".

I just posted a video of the Vaucanson AVA13 mechanical calculator. You don’t see these very often outside France. This one was used in the 1950s by the Dutch Royal Army at the barracks in Schoonhoven (havenkazerne). (1/2) youtu.be/16-o-QOOnvE

Let’s see what happens…

At the end of the 1950s the Comptometer Corporation (formerly Felt & Tarrant) was not doing well financially. They desperately needed a hit product, and came up with the Electrowriter. Two machines connected by a phone line, like a fax machines, but you could transmit live writing and drawing. (1/2)

Awesome 1936 ad for the Brunsviga mechanical calculator, which apparently was used aboard the Hindenburg zeppelin to calculate its course. The vessel flew for only 14 months till its disastrous crash in May 1937.