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Direct II

Introduction
My Direct II
How to use the Direct II
Direct II Video
Articles and Advertisements
Patents
Links

The company Moesch & Huber was founded by Carl Moesch and Hans Huber in Zürich in 1921 or earlier. They constructed the Demos calculator in about 1922, which had a toothed segment mechanism and was a cheaper alternative to pinwheel calculators. It was not very successful so they switched to producing the Direct calculator. This was made from about 1926, and later the similar but slightly improved version appeared, the Direct II. There was also a variant called the Direct L which was a listing machine, and the Direct EL which was an electrically driven version of the Direct L listing adding machine. All these variants seem to have been made in two different sizes, one that is 2 columns/digits wider than the other.

The company name shown on the Direct calculators is Theo Muggli AG, also based in Zürich. This company sold office equipment, mainly typewriters and calculators. It is unclear to me how much Theo Muggli himself was involved in the design and manufacturing of the Direct machines, but his company was the sole distributor of them. Theo Muggli died in 1933, but the company that was named after him continued after his death using the same name until it was finally dissolved in 1995.

My Direct II

The Direct and earlier versions of the Direct II had a black case with a green keyboard plate, and black and white keys. Later the colour of the Direct II was changed to dark brown, with a light brown keyboard and brown and white keys. The differences between the Direct and the Direct II are minor. The Direct had two buttons for selection of + and × mode, whereas the Direct II has a single switch. Also, the two buttons marked S'tot and Corr were combined into a single S/C button.

My Direct II is one of the later versions, so its casing is brown. It has 10 columns of keys, and a 10-digit register. Its serial number is 26509. It is not exactly known when these machines were produced, but it seems they were being made and sold until the 1950s.

How to use the Direct II

The Direct II has two registers. The display register generally shows the input, but there is also an internal register that keeps track of the result of the calculation, i.e. it holds the running total of all the numbers that were added or subtracted.

The controls are as follows:

• Crank: The crank on the right of the machine is used for displaying the result of a calculation. It copies the value stored in the internal register onto the visible display. When that internal register is displayed, the display window shows red lines along the top and bottom to indicate that this is so. If a number has been entered, then the crank is disabled until the number has been cleared or added.
• Keyboard: Use this to enter the number you want to add (or subtract), at most one key per column. When you press a key, it stays depressed. The value entered will show in the display. If the display is showing a total, then the keyboard is disabled.
• S/C button: Located to the left of the keyboard. This button has two uses. It clears an entered number from the keyboard (and the display) so you can correct any mistakes (on older version this is done by the Corr button). If the crank has been turned so that the display shows the running total, then pressing this button clears the display for the next input without affecting the running total (on older versions this is done by a separate S'Tot button).
• Minus button: Located to the top right of the keyboard. Press this before entering a number to indicate that the number is negative. You cannot press this button once you have started entering a number, so if you forget to press it beforehand you will have to clear the input (with S/C), press Minus, and enter the number again.
• Enter bar: The unmarked bar to the right of the keyboard has two uses. If a number has been entered, it will add the number to the internal register, and (usually) clear the keyboard/display ready for the next number to be entered. If the display is showing a total, then pressing the bar will reset the total to zero.
• +/× switch: This switch to the left of the keyboard is normally set to + for addition/subtraction. When it is set to ×, then the behaviour of the keyboard is changed to be like a direct adder. Any number you type is immediately added to the total, without needing to press the Enter bar. This allows you to do multiplication by repeatedly entering the number, in the style of a Comptometer. Note that if you press the Minus button, then the behaviour temporarily returns to normal.

Direct II video

Here is a video where I demonstrate my Direct II.

Articles and Advertisements

Here are a few articles about Theo Muggli and the Direct that I found in online archives.

Articles about Theo Muggli
(The Royal Standard, Royal Typewriter Company Inc., 1922-1924)

Direct
(Organisations-Lexikon, Walter le Coutre and Walter Thoms, 1930)

Direct
(Moderne Buero-Maschinen, 1931)

Direct
(Die Tat, 1941-04-24)

Here a few advertisements for the Direct, and several ads by Theo Muggli though they are mostly for typewriters.

Patents

Here are all the patents by Hans Huber and Carl Moesch that I was able to find. Only one seems to be for the Direct adding machine.

Links

• Rechenmaschinen-Illustrated shows a black Direct II and the listing variant Direct L.
• National Museum of American History's collection of adding machines includes a black Direct II that came from Dorr E. Felt's collection.
• Rechnerlexikon has an entry for the Direct II.
• American History Museum has a black Direct II.

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