The Hamann Manus looks like a pinwheel calculator, but it uses a different mechanism. At the front is a carriage containing a 13-digit main register on the right and an 8-digit counter on the left. In the main body are 9 input levers with an input register that displays the current lever settings. There is a large crank on the right, and a clockwise turn of that crank normally adds the input to the register, and increments the counter. There is a switch to the left of the input that changes the direction of the counter.
The main noticable difference from a normal pinwhweel machine is that the crank cannot be turned anti-clockwise. To subtract you must instead flick a switch located below the crank to set the machine in subtraction mode. This shifts the carriage a half step, thereby reconnecting the carriage register through a set of intermediate gears. A clockwise turn of the crank then subtracts the number because it turns the register digits in the opposite direction. There is a very small tab just below the counter direction switch with which the crank can be reversed. If for some reason the mechanism locks up and the crank cannot move forward, then you can push the tab to allow the crank to move backwards into its cradle so that the problem can be fixed more easily.
The carriage can be moved a step left or right using the arrow buttons next to the crank, or any amount using the knob on the front of the carriage. The clearing levers for the register and counter are both on the right of the carriage. The input can be cleared with a lever that lifts a bar that pushes the input pins up to zero. That bar can be made to lift every time the crank is turned so that the input is cleared automatically after each addition or subtraction. You can enable this with the small switch on the side of the bar, or disable it for multiplication or division.
Over the years that the Manus was in production, small improvements were made. These variations are unofficially denoted with the letters A to F. Mine is a type F with serial number 15421.
This machine has automatic division. Set up the numerator in the register (as many decimal places to the left as possible). Then shift the carriage as far to to the right, and push in the carriage knob. Set the input to the denominator, again at the left end. Set the counter direction switch to subtract, and clear the counter. Then simply repeatedly turn the crank. Whenever the register underflows, the carriage is moved a half-step to the left so that the next turn adds the denominator back. This then overflows the register and moves the carriage another half-step, ready to subtract from the next decimal position. This repeats until the carriage arrives at the far left location, where the register is disconnected and further turns of the crank have no effect.
The latched gear mechanism of the Manus is somewhat reminiscent of the Marchant XA. Instead of pinwheels in which the number of teeth vary, it uses gear wheels that can connect to or disconnect from the central axle. While the crank turns the axle around, the stationary setting lever acts like a cam, and the cam follower on the rotating axle then either locks or unlocks the gear. In effect the gear rotates by an amount that is proportional to the lever setting.
Below is a video I made that demonstrates the Hamann Manus.
Christel Hamann (1870-1946) was a highly prolific and inventive designer of calculating machines. He founded his own company in 1896, at which his first machines were made. The full range of his lesser known early work is somewhat unclear. It is possible that he started with troncet adders and pinwheel machines, as his name has been linked to the Trick (troncet adder) and the Berolina (pinwheel machine) due to some of his patents. His first proper machine design was called the Gauss, and was a cylindrical machine with a single stepped drum at the centre and number wheels arranged around it. He patented this in 1902. This principle had been used by Philipp Matthäus Hahn in the 1770s to make a handful of machines, but the Gauss was simpler, and about a thousand were made. The culmination of the principle was the Curta calculator from 1946 by Curt Herzstark.
In 1905 he developed and patented an entirely new principle, proportional levers. Similar to stepped drum machines the input is done by sliders, one for each digit, and the slider shifts a gear along an axle so that it engages with the mechanism. In this case that is not a stepped drum for each digit, but a set of ten parallel toothed racks shared by all the input digits. These toothed racks are pivoted to an arm, and when one end of that arm swings out, the racks move different amounts, varying from 0 to 9 units. The register wheels move in one direction only, so when the racks have returned to their starting position the input has been added to the register. For subtraction the other end of the arm is moved so that complementary digits are added. Hamann called this machine the Euklid.
In 1907 Hamann's company was bought by Mercedes Bureaumaschinenwerke. They continued to make the Gauss for a few years, but it was mainly the Euklid machines that became successful and were developed further. Mercedes-Euklid variants, all based on the same principle, were produced until the 1960s.
In 1922 Hamann started working for Deutsche Telephonwerke GmbH, or DTW, which later became Deutsche Telephonwerke und Kabelindustrie AG, or DeTeWe. It seems that he essentially ran a daughter company Hamann Rechenmaschinen. There he developed the Hamann Manus, of which the model A was released in 1925. It seems that before then only Madas had made machines with automatic division, but they were much larger machines. This was the first compact calculator with automatic division. There followed models B to F, and finally R. See the description of my Manus F above for more details about the mechanism. Below is a table with information about these Hamann Manus models. Unless otherwise specified, later models in the table also have all the characteristics of the previous models.
|A||1925-1926||501- 1000||Black colour; DTW logo; Wingnuts for clearing; Input clearing button at top-left; Carriage left-shift lever on the right, no right-shift lever; Overflow bell on outside.|
|B||1926-1927||1001- 1500||Carry mechanism in counter; Crank reverse tab|
|C||1927-1937||1501- 8200||Carriage right-shift lever on the left; Overflow bell internal|
|D||1937-1944||8200-12000||Both carriage shift buttons next to crank on right; Wingnuts replaced by clearing levers at each end of carriage.|
|E||1948-1953||12001-15000||No toothed rack visible in base; At some point changed to green colour, DeTeWe logo.|
|F||1953-1955||15001-16000||Green colour; DeTeWe logo; Both clearing levers on right of carriage; External input clearing bar|
|R||1953-1959||40001-54000||Back transfer mechanism|
In his time at DeTeWe Christel Hamann also developed many other machines such as the Selecta, Delta, Elma, and various Automat models. He also experimented with relays used by telephone industry, and in 1931 patented one of the earliest electric calculators using that technology. Hamann died in 1946. In 1958 DeTeWe sold off Hamann Rechenmaschinen GmbH to Marchant. This occurred at the time that Marchant fused with Smith-Corona to become SCM, so Hamann Rechenmaschinen GmbH became a wholly owned daughter company of SCM.
Handhabung der Hamann Manus Rechenmaschine (PDF, 10.7 MB)
Deutsche Telephonwerke und Kabelindustrie A.-G.
48 page stapled booklet
226mm × 156mm
This booklet is the manual for the Hamann Manus in the German language. It has no copyright year, but the pictures are of the model D so it was presumably printed between 1937 and 1944.
I have not found many articles and advertisements relating to the Hamann machines in online archives.
Here is the entry in Ernst Martin's 1925 book Die Rechenmaschinen:
Here are a few other articles that mention Hamann.
Lastly, here are some advertisements. The first one is for the Gauss, the last includes a Marchant Hamann.
|Patent||Filing date||Published date||Name||Description|
|DE 88,223||11-06-1895||10-09-1896||Christel Hamann||Planimeter|
|US 703,785||02-07-1900||01-07-1902||Christel Hamann||Gauss predecessor|
|US 705,838||28-03-1902||29-07-1902||Christel Hamann||Extra register for pinwheel calculator|
|US 772,935||13-10-1903||25-10-1904||Christel Hamann||Pinwheel calculator improvements|
|DE 179,246||26-11-1904||30-11-1906||Christel Hamann||Subtraction using complements on pinwheel calculator|
|DE 194,527||23-03-1905||06-02-1908||Christel Hamann||Gauss calculator
See also: US 832,666
|DE 209,817||31-05-1906||13-05-1909||Mercedes Bureau-Maschinen-Gesellschaft m.b.H.||Euklid calculator
See also: US 1,011,617
|DE 210,524||30-10-1907||03-06-1909||Mercedes Bureau-Maschinen-Gesellschaft m.b.H.||10-key input|
|DE 210,661||11-02-1908||07-06-1909||Ch. Hamann, Math. Mech. Institut, G.m.b.H.||Subtraction mode on Gauss calculator|
|DE 228,563||04-06-1909||12-11-1910||Ch. Hamann, Math. Mech. Institut, G.m.b.H.||Calculator for products of more that two factors|
|DE 234,984||15-09-1910||29-05-1911||Ch. Hamann, Math. Mech. Institut, G.m.b.H.||Calculation device for trigonometric functions|
|DE 242,665||13-04-1911||16-01-1912||Mercedes Bureau-Maschinen-Gesellschaft m.b.H.||Trick, troncet with sliding cover for subtraction|
|DE 253,525||24-06-1911||13-11-1912||Ch. Hamann, Math. Mech. Institut, G.m.b.H.||Printing mechanism|
|US 1,221,318||20-04-1912||03-04-1917||Ch. Hamann, Math. Mech. Institut, G.m.b.H.||Calculator with fast multiplication|
|DE 268,729||12-04-1913||27-12-1913||Mercedes Bureau-Maschinen-Gesellschaft m.b.H.||Trick, version for British currency|
|DE 278,680||12-04-1913||02-10-1914||Ch. Hamann, Math. Mech. Institut, G.m.b.H.||Calculator with totaliser|
|DE 287,770||17-02-1914||05-10-1915||Ch. Hamann, Math. Mech. Institut, G.m.b.H.||Euklid with automatic multiplication and division
See also: US 1,566,961
|DE 367,726||24-10-1920||25-01-1923||Deutsche Telephonwerke G.m.b.H.||Latched gear mechanism|
|US 1,528,018||17-01-1921||03-03-1925||Mercedes Bureau-Maschinen- und Waffenwerke||Combined typewriting and counting machine|
|US 1,566,962||01-06-1923||22-12-1925||Mercedes Bureau-Maschinen- und Waffenwerke||Calculator with fast multiplication|
|DE 418,445||29-01-1925||11-09-1925||Deutsche Telephonwerke und Kabelindustrie A.G.||Electric drive
See also: SE 64,082 C; US 1,912,133
|DE 432,435||19-12-1924||05-08-1926||Deutsche Telephonwerke und Kabelindustrie A.G.||Automatic division
See also: SE 64,634 C; US 1,788,192
|DE 443,479||04-03-1926||29-04-1927||Deutsche Telephonwerke und Kabelindustrie A.G.||Revolution counter|
|DE 468,275||04-03-1926||09-11-1928||Deutsche Telephonwerke und Kabelindustrie A.G.||Carry mechanism for revolution counter|
|DE 470,339||24-10-1926||11-01-1929||Deutsche Telephonwerke G.m.b.H.||Shortcut multiplication|
|DE 502,276||04-03-1926||12-07-1930||Deutsche Telephonwerke und Kabelindustrie A.G.||Electric drive|
|DE 531,178||14-07-1929||07-10-1931||Deutsche Telephonwerke und Kabelindustrie A.G.||Automatic multiplication
See also: SE 76,452 C
|US 1,968,201||15-03-1930||31-07-1934||Deutsche Telephonwerke und Kabelindustrie A.G.||Automat calculator|
|DE 615,334||31-10-1933||03-07-1935||Deutsche Telephonwerke und Kabelindustrie A.G.||Short-cut automatic multiplication
See also: US 2,170,406
|DE 648,137||12-11-1931||22-07-1937||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Selecta calculator
See also: GB 437,743; SE 82,799 C; US 2,081,008
|DE 649,083||16-02-1931||25-08-1937||Deutsche Telephonwerke und Kabelindustrie A.G.||Casing|
|DE 691,209||24-02-1937||20-05-1940||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Electrically driven carriage|
|DE 711,641||22-04-1931||14-10-1941||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Electric calculator|
|DE 724,330||27-08-1937||31-10-1942||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Electrically driven calculator
See also: SE 100,538 C
|DE 728,515||03-11-1933||28-11-1942||Deutsche Telephonwerke und Kabelindustrie A.G.||Selecta calculator improvement
See also: GB 437,743; SE 82,799 C; US 2,081,008
|DE 741,559||21-03-1931||18-11-1943||Deutsche Telephonwerke und Kabelindustrie A.G.||Electric calculator|
|DE 742,464||07-09-1939||25-04-1944||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Calculator|
|DE 742,466||05-11-1940||19-04-1944||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Revolution counter
See also: SE 106,919 C
|DE 746,804||11-03-1938||25-08-1944||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Keyboard Input|
|DE 748,500||23-10-1940||03-11-1944||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Backtransfer
See also: SE 106,999 C
|DE 756,999||07-09-1939||21-06-1954||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Calculator|
|DE 759,321||23-10-1940||22-02-1954||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Calculator|
|DE 819,592||29-10-1949||05-11-1951||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Carry delay mechanism|
|DE 861,935||02-07-1941||08-01-1953||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Backtransfer copy|
|DE 862,524||31-08-1943||12-01-1953||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Multiple registers|
|DE 866,268||21-01-1939||09-02-1953||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Automatic carriage movement for shortcuts
See also: SE 107,529 C
|DE 866,563||15-11-1939||12-03-1953||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Extra register (Selecta SP)|
|DE 867,010||11-09-1942||12-02-1953||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Carry mechanism for extra register|
|DE 869,876||05-03-1938||09-03-1953||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Transfer mechanism|
|DE 909,260||12-10-1941||15-04-1954||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Transfer mechanism|
|DE 919,787||29-10-1949||04-11-1954||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Backtransfer Manus R|
|DE 919,790||28-08-1937||04-11-1954||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Quotient transfer mechanism|
|DE 924,717||02-03-1941||07-03-1955||Christel Hamann; Deutsche Telephonwerke und Kabelindustrie A.G.||Printing mechanism|
|DE 1,799,980 U||29-03-1958||12-11-1959||Hamann Rechenmaschinen GmbH||Hamann Automatic 500|
Rechnerlexikon has a page for the
Hamann Manus A-F, the
Hamann Manus R, and
has some material about
Rechenmaschinen-Illustrated has a page about Hamann calculators, and also an English translation of the Hamann Manus manual.
The history of Computing has a biography page for Christel Hamann
Tiny Henst's collection includes a Manus R
Cris Vandevelde has a Manus C
Christian Hamann has a Manus C, Manus D, Manus R
Wolf-G Blümich has a page about the Hamass Manus, as well as a detailed Table of Manus models.
Rechenwerkzeug.de has a page listing the Hamann DeTeWe machines.
© Copyright 2019 Jaap Scherphuis, mechcalc a t jaapsch d o t net.