Motor drive
Prior to May 9, 1901, there is no record of any recording-adder having been operated by electric motor drive. But on that date Frank C. Rinche applied for a patent showing such a combination with the recorder, which became commercially known as the Universal Accountant. The patent, No. 726,803, was issued April 28, 1903, and is the first of a series issued to Rinche on various combinations of mechanical driving connections.
Distinguishing marks for clear, totals and sub-totals
A feature common to recording of added columns of numerical items is the distinguishing characters for clear, sub-totals and totals by the use of letters, stars and other marks. The first patent on anything of this nature that has come into general use was applied for June 9, 1903, by A. Macauley, and was issued June 12, 1906. This patent is No. 823,474, and shown connected with the Burroughs recorder to register with a star when the first item is printed if the machine is clear and when a total is printing. Provision was also made for printing an S when a sub-total was printed.
Adding cut-out
The use of recording-adders is often applied when it is desired to record dates along with tabulating added columns of recorded items. Of course there is no use of adding the dates together, and again if they were allowed to be added to the totals an erroneous total of the columns added may result under certain conditions. Means for automatically cutting out additions at certain positions of the paper carriage in cross-line tabulating was devised by H. C. Peters, and a patent showing such combination operative on the Burroughs recorder was applied for by him May 12, 1904. The patent, No. 1,028,133, was issued June 4, 1912.
Self-correcting keyboard
With the introduction of the key-set crank-operated feature on the Felt Comptometer, the key action, like in the Burroughs recorder, became a feature to be considered; but unlike the organism of the Burroughs, the Felt construction allowed of the use of a self-correcting keyboard without the possibility of error occurring from its use. This feature is shown in a patent issued to Felt & Wetmore applied for December 27, 1904, and issued May 14, 1907. The patent number is 853,543, and provides a means of correcting errors made in setting the keys by merely depressing the proper key or keys, which will release any previously set in the respective orders.
Split keyboard
In some classes of recording it is desirable to print more than one column of items without shifting the paper carriage laterally. A means providing for such an emergency is shown in patent No. 825,205, issued to C. W. Gooch July 3, 1906. The patent was applied for December 2, 1905, and shows a means applicable to any order that may intercept the printing of the ciphers in that order, and thereby the ciphers in all other orders to the right from any key depression to the left of such order. This made what has been generally known as the split keyboard, but differs from that now in general use in that it was set to certain orders and not selective at the will of the operator.