Part 12

While with such a combination it may be possible to provide a set pressure great enough to legibly print a numerical item or total having eight to ten figures through an ink ribbon, it would not be practical to use the same pressure to print a single-digit figure, as it would cause the type to break through the paper. And yet in the numerical items and totals that have to be recorded in machines of the class under consideration, such wide variation is constantly encountered.

We are all familiar with the typewriter and the legible printing it produces. But suppose instead of printing each letter separately the whole word should be printed at once by a single-key depression, then, of course, single-letter words, such as the article “a” or the pronoun “I” would also have to be printed by a single-key depression. In this supposition we find a parallel of the requirements of a recording-adding machine.

If it were possible to so increase the leverage of the typewriter keys enough to cause a word of ten letters to be printed as legibly as a single letter is now printed, ten times the power would have to be delivered at the type-head. Then think what would happen with that same amount of power applied to print the letter “a,” or letter “I.” You would not question that under such conditions the type would break a hole in the paper. And yet the patentees of the said described inventions wanted the public to believe that their inventions were operative. But to be operative as recording-adding machines, they must meet such variable conditions as described.

It is useless to believe that a variation of from one to ten or more type could be printed by a set amount of pressure through an ink-ribbon and be legible under all circumstances.

While the needle-type of Pottin may have printed the items legibly enough for a cash register, it would not serve the purpose of a record for universal use. The use of regular type and the inking ribbon proposed in his specification would bring it within the inoperative features named.

THE LUDLUM MACHINE

In 1888, about two months prior to the issue of the Burroughs recording machine patent just referred to, a patent was issued to A. C. Ludlum for an adding and writing-machine. (See illustration on opposite page.)

It will be noted by reference to the drawings that the scheme is that of a typewriter with an adding mechanism attached.

The details of the typewriter may be omitted, as most of us are familiar with typewriters. A feature that differed from the regular typewriter, however, was that the machine printed figures only and the carriage operated in the opposite direction, thus printing from right to left instead of left to right.

A series of numeral wheels and their devices for the transfer of the tens, designed to register the totals, are shown mounted in a shiftable frame connected with the bar marked F, with the typewriter carriage, and is claimed to move therewith.

Each numeral wheel is provided with a gear marked G, which, as the carriage moves after writing or printing each figure of the item, is supposed to slide into mesh one at a time with an adding gear marked H, the engagement taking place from right to left. Or beginning with the right or units numeral wheel a higher order numeral wheel gear is supposed to shift through movement of the carriage into engagement with the adding gear H, each time a key is depressed.

The adding gear H, is supposed to receive varying degrees of rotation from the keys according to their numerical marking and to rotate the numeral wheel with which it happens to be engaged, a corresponding number of its ten marked points of registration.

Between the adding gear H, and the keys which act to drive it, is a ratchet and gear device consisting of the ratchet pawl pivoted to the adding gear H, the ratchet I⁶, and its pinion gear, the segment gear I² fast to the rock shaft I, the nine arms I¹ fast to the rock shaft and the pins I², which are arranged in the key levers to contact with and depress the arms I¹ of the rock shaft varying distances, according to the value of the key depressed. That is, supposing that the full throw of the key-lever was required to actuate the rock shaft with its gear and ratchet connection to give nine-tenths of a revolution to the numeral wheel in adding the digit nine, the pin I² in the (9) key-lever would in that case be in contact with its arm I¹, of the rock shaft, but the pins I², of each of the other key levers would be arranged to allow lost motion before the pin should engage its arm I¹ of the rock shaft, in accordance with the difference of their adding value.

According to the specification, Ludlum evidently had the idea that he could stop the adding gear H, while under the high rate of speed it would receive from a quick depression of a key, by jabbing the detent J between the fine spacing of the gear teeth shown in his drawing. But to those familiar with the possibility of such stop devices, its inoperativeness will be obvious; not that the principle properly applied would not work, for its application by Felt prior to that of Ludlum proved the possibilities of this method of gauging additive actuation.

The detent lever J, as shown in the drawings, is operated by the hinged plate D, through action of the key levers, as any one of them are depressed.

Under depression of a key, the hinged plate D, being carried down with it, engages the arm J³ of the detent and throws the tooth at its upper end into the teeth of the gear H.

The timing of the entry of the tooth of the detent is supposed to be gauged to enter the right tooth, but as the action of these parts is fast, slow or medium at the will of the operator, considerable time must be allowed for variation in the entry of the detent tooth, which requires space, as certain parts will fly ahead under the sudden impact they may receive from a quick stroke, where they would not under a slow stroke, but no allowance was provided for such contingency.

The means provided for the carry of the tens consist of the gears G⁹, meshing with the numeral wheel gears and the single gear tooth g⁹, attached to it, which, at each revolution of the lower wheel, as it passes from 9 to 0, engages the gear of the numeral wheel of higher denomination and was supposed to turn the higher gear one-tenth of a revolution, thus registering one greater.

On account of the Gears G⁹, of one order and the gear tooth g⁹, of another order operating on the same numeral wheel gear, the transfer gears are arranged alternately on separate shafts, one at the side and one below the numeral wheels.

The mechanical scheme disclosed in the Ludlum patent, to the unsophisticated may seem to be operative. But to those familiar with the Art of key-driven adding mechanism it will at once be obvious that even if the typewriter feature was constructed properly the possibility of correctly adding the items as they were printed was absolutely impossible.

Laying aside several other features of inoperativeness, obvious to those who know such mechanism, the reader, although not versed in the Art of key-driven adding mechanism, will observe from the preceding chapter, that the means provided for transferring the tens without any control for the numeral wheels against over-rotation, would make correct addition impossible.

The drawings and specification of the Ludlum patent disclose a mere dream and show that they were not copied from the make-up of an operative machine.

It was a daring scheme and one that none but a dreamer would undertake to construct in the method shown. There have in later years been some successful ten-key recording machines made and sold, but they were of a very different design and principle.

There have also been several adding attachments made and sold that could be adjusted to a regular commercial typewriter that are claimed to be dependable, but none of these machines were early enough to be claimed as the first operative recording-adding machine, or the first adding machine in which the principle used for the legible recording of the numerical items used in the machines of today may be found.

FIRST PRACTICAL RECORDERS

The fact that Barbour, Baldwin, Pottin, Ludlum and Burroughs attempted to produce a recording-adding machine shows that as far back as 1872, and at periods down to 1888, there was at least in the minds of these men a conception of the usefulness of such a machine, and the fact that there were five with the same thought is fairly good evidence of the need for a machine of this class.

In some of the human-interest articles issued through the advertising department of the Burroughs Adding Machine Co. it is stated that Wm. Seward Burroughs was a bank clerk prior to his efforts at adding machine construction. It is conceivable, therefore, that his first efforts at adding machine invention should be directed toward the production of a machine that would be of service in the bank for the bringing together of the loose items of account that are to be found in the form of checks, drafts, and the like, by printing a record of the items and their totals during the process of adding them together.

It is not surprising, therefore, that a manufacturer of a successful calculating machine should, through his contact with the trade, come to the conclusion that there was use for a machine of this class in the banks. As proof of this, we find that an application for a recording-adding machine patent was filed January 19, 1888, by D. E. Felt, which was allowed and issued June 11, 1889.