RAILWAY mceisrss MANUF,G co. ·v. THIRD Avm. RY. co. 37
commence the registry of fares to be collected on the return trip of the
car or vehicle." The detailed description coincides with devices thus
organized, and there is nothing in the specification to denote or imply
that registering mechanism having this mode of operation is a preferable
or subsidiary as distinguished from an essential feature. Unless het
registering mechanism is of this character, it cannot co—operate with het
direction indicator in performing the functions assigned to the latter, be-
cause the direction indicator is required to be so organized that it can-
not be changed without bringing the primary register to zero and trans-
ferring its record to the secondary register.
The first and second claims are intended to discriminate between a
combination in which the direction indicator cannot be changed without
causing a transfer to be made from the trip register to the permanent
register, and one in which it can be changed by being brought to zero
without causing such a transfer. In either combination, a locking de-
_vice by whichthe indicator cannot be changed unless the trip register be
brought to zero, is indispensable. The second claim contains the fur-
ther constituent of a casing to inclose the other parts. The fourth claim
contains the additional constituent of a casing provided with openings.
The fifth claim embodies all the constituents of the fourth together with
alarm mechanism, and actuating mechanism for working the register and
alarm machanism. It is tobe observed that infringement of the third ,
claim is not alleged, and that it differs from the first claim as that claim
must be construed, only in a more particular specification of the parts _
required to make a permanent record of the fares collected, that is, in U
specifying the mode of operation of the co-operative devices. It would
seem that this claim more particularly and distinctly points out the real
invention of Harris than do the first or second claims. _
There is some doubt whether the first and second claims are not void
for want of novelty in view of the Morgan-Brown patent. There is room
for fair argument that they are expressed in terms to comprehend, the
first, any fare register having the direction indicator of the Harris patent,
and the second, any registering mechanism of a fare register combined
with such a direction indicator. The general statement in the patent of
the essential features of the several inventions which are the subject of the
patent, and the very guarded terms of the disclaimer at the end of the
description, countenances the argument that these claims were intended
to be as broad as their literal terms. The claim of the inventor in let-
ters patent must be construed according to its terms; and, when its im-
port is plain, resort cannot be had to the context for the purpose of en-
larging it. A more liberal rule is indulged frequently when it is neces-
sary to restrict or narrow the ordinary import of the language in order to
secure the real invention of the patentee, and, preserve the claim from `
destruction. But the language of the supreme court in White v. Dtmbmr,
119 U. S. 47 , 52, 7 Sup. Ct. Rep. 72, is applicable to both classes of
cases. The court say:
- " The claim is a statutory requirement, prescribed for the very purpose of
making the patentee define precisely what his patent is; and it is unjust to