Jaap's Mechanical Calculators Page

Seidel & Naumann

The SuN Adder

The SuN Adder
Seidel & Naumann
Newspaper and Magazine Articles and Advertisements

The SuN Adder

The SuN Adder is a chain adder which was made in Germany from about 1910 until the early 1920s. My SuN Adder has serial number 10451. It comes in a nice case, and with a stylus made of Bakelite with a metal tip.

The SuN Adder
The SuN Adder, front
The SuN Adder, serial number
The SuN Adder, logo
The SuN Adder, logo
The SuN Adder, register
The SuN Adder, decimal pointer
The SuN Adder, chains
The SuN Adder, input lever
The SuN Adder, input lever A
The SuN Adder, input lever M
The SuN Adder, stylus
The SuN Adder, stylus triangle
The SuN Adder, stylus hook
The SuN Adder, stylus hook
The SuN Adder, box
The SuN Adder, in box
The SuN Adder, clasp closed
The SuN Adder, clasp open
The SuN Adder, box logo

It has a register consisting of 9 parallel number wheels on a single axle. This is the most common size, but there is also a 13-digit version as well as special versions for British currency. Each wheel in the register is driven by teeth attached to a chain belt that passes underneath the wheel. On the front of the machine is an open panel which gives access to the nine chains. The visible chain links are numbered, having the digits 1 to 9 engraved on them. You can use a stylus to pull a numbered link all the way down to the bottom of the panel. This adds the chosen digit to that digit in the register, and the register will automatically carry when a digit exceeds 9.

The chains that you pull down remain in position so that you can read off the number you entered on the bottom row of the visible chain links. To add the next number you first have to clear the input by pressing A on the small lever at the front right of the machine. This releases the chains, allowing them to spring back up without affecting the number in the register.

There is a lever in the right side of the machine next to the register. By pulling this lever forward the register can be reset.

The chains and register wheel only move in one direction, so subtraction can only be done through the addition of complementary numbers. On the side of the chain panel the complementary digits are displayed. For the right hand column use the complementary digit shown on the right of the panel, and for all the other columns use the complementary digit shown on the left.

The small lever marked M is for multiplication. If this is pressed down it will lock in place so that input is cleared immediately without needing to press A every time.


Seidel & Naumann

This adder was made by Seidel and Naumann. In 1868 in Dresden, Karl Robert Bruno Naumann zu Königsbrück founded a company based around his small mechanics workshop. There he made sewing machines similar to Singer. A year later the businessman Erich Seidel heavily invested in the company, at which point it was renamed Seidel und Naumann. That name remained even after Seidel left in 1876.

1908 Jahrbuch der Automobil und Motorbootindustrie

As the company grew rapidly, it diversified to other products:

In 1905 they even produced a rally car, though that does not seem to have led to commercial car production.

The X×X calculator was based on the classic Thomas de Colmar machine, the Arithmometer, but included a variant with buttons instead of sliders for inputting numbers. The X×X and the SuN were both designed by Bernhard Carl Max Behr, who led the calculator division of the company. It seems he left very soon to set up his own calculator business. He died in 1917.

The company was able to rebuild after sustaining major damage in the bombing of Dresden in 1945, but then seems to have specialised in typewriters only. In 1951 it merged with Clemens Miller AG to become VEB Schreibmaschinenwerk(e) Dresden. The "Erika" line of typewriters was made until 1991 after which the company was liquidated.

Newspaper and Magazine Articles and Advertisements

I haven't found any adverts specifically for the SuN adder, but there are some ads from the early 1910s for Seidel & Naumann's other products. The two older Dutch items are an announcement of the trademarks that S&N is about to use to start selling their "improved Singer" sewing machines in the Netherlands, and a reply notification from Singer's lawyer that they are not allowed to use the Singer name in any way to sell their machines.

1879-05-13 Algemeen Handelsblad
1879-06-01 Algemeen Handelsblad
1911-07-24 Berliner Tageblatt
1912-10-14 Berliner Tageblatt


Here are the patents relating to the SuN chain adder. Bernhard Behr based his design on the chain adder devised by Henry Goldman a decade earlier.

PatentFiling datePublish dateNameDescription
GB 1899 10,23715-05-189914-04-1900Henry GoldmanChain adder
GB 1908 03,40214-02-190815-02-1909Bernhard Carl Max BehrChain adder with two registers
GB 1911 18,73719-08-191111-04-1912Bernhard BehrChain adder. See also:
AT 55,820 B; US 1,096,012; CA 138,507; FR 433,170
GB 1912 09,01316-04-191216-01-1913Seidel & NaumannCarry mechanism. See also:
AT 61,025 B; FR 443,000


Rechnerlexikon has pictures of a 13-column version of the SuN adder.
Rechnen Ohne Strom shows several types of chain adders.
Rechenwerkzeug has the German manual for the SuN adder.

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