Burroughs Adding Machine, 1905
William S. Burroughs (1855-1898) invented an adding and listing machine with a full keyboard in the early 1880s, co-founded the American Arithmometer Co. in 1886 to produce the machine. After its Bankers' and Merchants' Registering Accountant machine failed in trials in 1890, the American Arithmometer Co. marketed its improved Burroughs Registering Accountant in 1892 for $475.
Final Total
The instruction booklet for the Burroughs Registering Accountant directs the operator requiring a total to “first execute one complete movement of the operating lever with no keys depressed. Then depress the total key and hold same depressed during a second complete movement of the operating lever.” The initial movement of the operating lever in this step returns the racks to their normal position. Due to the carrying process, some of the racks may be one tooth above their normal position. Pulling the operating lever without first depressing any of the keys accomplishes the racks’ return, so that a final total can be obtained.
Pressing the total key has the effect of reversing the mechanism which pushes and pulls the recording pinions into and out of gear with the racks. As you recall from step 1 of the "Reverse Stroke" operation described in Step by Step, the act of pulling the machine’s operating lever causes the wheels to be pulled out of gear. Therefore, the “reversing effect” of the total key enables the recording pinions to remain in place as the racks descend, thus retaining the sums they have been “recording.” After the bank clerk operating our machine presses the total key and pulls the operating lever forward, the racks descend. During this descent, the racks turn their respective recording pinions back to zero. In so doing, each rack causes the sector attached to it to turn through the numerical distance corresponding to its own recording pinion, which makes the appropriate typeface come up and print. If the bank clerk first mentioned in Step by Step wants to clear his Burroughs Registering Accountant for the purpose of entering a new string of numbers and then printing their sum total, he must continue depressing the total key while returning the operating lever to its original position. This will cause the recording pinions to remain out of gear and in their zero positions during the descent of the racks. The retention of these zero positions enables the bank clerk to deem his Registering Accountant “clear.”
However, if he wants to continue adding figures to the sum total, the bank clerk must allow the machine to hold the sum in its mechanical memory. In that case, he releases the total key before returning the operating lever to its starting position. In so doing he places the mechanism which throws the recording pinions in and out of gear in its original “unreversed” position. If you look back at step 2 of the "Reverse Stroke" operation explained in Step by Step, you will note that the recording pinions slip into gear when the operating lever is pushed back. The racks then return the pinions to their original positions, and thus the machine still retains the sum.
From the abacus to the graphing calculator, it is amazing to see how far we have come with computation machines as we transition from mechanical to electronic. Now we no longer need to spend years learning the inner workings of arithmetic and focus on learning more complex mathematics. But, as a math tutor, I see many people so dependent on their calculators that they do not trust themselves to add simple numbers in their head. Cases like these, and this machine makes me think that just sometimes it is better to do things by hand.
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