The illustration of the Bouchet machine on the opposite page was
reproduced from the drawings of the patent which is the nearest to the
machine that was placed on the market. The numeral wheels, like most of
the single-digit adders, are three in number, and consist of the prime
actuated, or units wheel, and two overflow wheels to receive the carry
of the tens. The units wheel has fixed to it a long 10-tooth pinion or
rotor I, with which nine internal segmental gear racks L, are arranged
to engage and turn the units wheel through their nine varying additive
degrees of rotation.
[Sidenote: _Description of Bouchet machine_]
The segmental gear racks L, are normally out of mesh with the pinion
I, and are fast to the key levers E, in such a manner that the first
depression of a key causes its rack to rock forward and engage with the
pinion I, and further depression moves the rack upward and rotates the
pinion and units numeral wheel. It will be noted that this engaging and
disengaging gear action is in principle like that of Robjohn.
The transfer devices for the carry of the tens, as already stated,
belong to that class of mechanism commonly known as the “Geneva
motion.” It consists of a mutilated or one-tooth gear fast to the units
wheel operating with a nine-tooth gear, marked D¹, loosely mounted on
an axis parallel to the numeral wheel axis. Each revolution of the
units wheel moves the nine-tooth gear three spaces, and in turn moves
the next higher numeral wheel to which it is geared far enough to
register one point or the carry. A circular notched disc, marked S, is
fast to the units wheel, and the nine-tooth gear D¹, has part of two
out of every three of its teeth mutilated or cut away to make a convex
surface for the notched disc to rotate in.
With such construction the nine-tooth gear may not rotate or become
displaced as long as the periphery of the disc continues to occupy
any one of the three convex spaces of the nine-tooth gear. When,
however, the notch of the disc is presented to the mutilated portion
of the nine-tooth gear, the said gear is unlocked. This unlocking
is coincident to the engagement of the single tooth of the numeral
wheel-gear with the nine-tooth gear and the passing of the numeral
wheel from 9 to 0, during which the nine-tooth gear will be moved three
spaces, and will be again locked as the notch in the disc passes and
the periphery fills the next convex space of the mutilated nine-tooth
gear.
[Sidenote: _Bouchet machine marketed_]
The Bouchet machine was manufactured and sold to some extent, but
never became popular, as it lacked capacity. Machines of such limited
capacity could not compete with ordinary accountants, much less with
those who could mentally add from two to four columns at a clip.
Aside from the capacity feature, there was another reason why these
single-order machines were useless, except to those who could not
add mentally. Multiple forms of calculation, that is, multiplication
and division, call for a machine having a multiplicity of orders.
The capacity of a single order would be but 9 × 9, which requires no
machine at all--a seven-year-old child knows that. To multiply 58964
× 6824, however, is a different thing, and requires a multiple-order
calculator.
[Sidenote: _Misuse of the term “Calculating Machine”_]
It is perhaps well at this time to point out the misuse of the term
calculating where it is applied to machines having only a capacity
for certain forms of calculating as compared with machines which
perform in a practical way all forms of calculation, that is,
addition, multiplication, subtraction and division. To apply the term
“calculating machine” to a machine having anything less than a capacity
for all these forms is erroneous.
An adding machine may perform one of the forms of calculation, but to
call it a calculating machine when it has no capacity for division,
subtraction or multiplication, is an error; and yet we find the U. S.
Patent Office records stuffed full of patents granted on machines thus
erroneously named. The term calculating is the broad term covering all
forms of calculation, and machines performing less should be designated
according to their specific capacities.
It is true that adding is calculating, and under these circumstances,
why then may not an adding machine be called a calculator? The answer
is that it may be calculating to add; it may be calculating to either
subtract, multiply or divide; but if a machine adds and is lacking in
the means of performing the other forms of calculation, it is only part
of a calculating machine and lacks the features that will give it title
to being a full-fledged calculator.[1]
[1] NOTE: The title of this book does not coincide with the above
argument, but in view of the common use of the term “calculating” its
application is better understood.
Considerable contention was raised by parties in a late patent suit as
to what constituted the make-up of a calculating machine. One of the
attorneys contended that construction was the only thing that would
distinguish a calculating machine. But as machines are named by their
functioning, the contention does not hold water. That is to say: A
machine may be a calculating machine and yet its construction be such
that it performs its functions of negative and positive calculation
without reversal of its action.
Again, a machine may be a calculating machine and operate in one
direction for positive calculation and the reverse for negative
calculation. As long as the machine has been so arranged that all forms
of calculation may be performed by it without mental computation, and
the machine has a reasonable capacity of at least eight orders, it
should be entitled to be called a calculating machine.
[Illustration: Drawings of Spalding Patent No. 293,809]