lement for the purpose of
its well recognized capacity, and then associates with it another
mechanical element for its recognized capacity, but so associates the
two elements that one has a modifying effect upon the capacity of the
other element, then the association will be capable of a result
greater than the sum of the results for the individual elements. This
excessive result is not due to the individual elements, but to the
combination of them. One has been added to one and a sum greater than
two has been secured. The modification of result may be due merely to
the bringing of the two elements together, so that they may mutually
act upon each other, or it may be due to the manner or means by which
they are joined. In a patentable combination the separate elements
mutually act upon each other to effect a modification of their
previous individual results, and secure a conjoint result greater than
the sum of the individual results. The elements of a combination need
not act simultaneously; they may act successively, or some may act
without motion. As an illustration, assume an old watch in which there
was a stem for setting the hands, and assume another old watch with a
stem for winding the spring. If an inventor should make a watch, and
provide it with the two stems, he would have only an aggregation. But
if he employed but one stem, and so located it that it could be used
at will for setting the hands or for winding the spring, then he would
have produced a combination. The particular instance just given is not
a case of the same number of elements, producing a result in excess of
the individual results of the separate elements, but is rather a case
of a lesser number of elements, producing a combination result equal
to the sum of the previous results of a greater number of elements. A
better example would perhaps be a new watch with its two old stems so
related that either could be used for setting the hands or for winding
the spring.

GENERA AND SPECIES.

An inventor, being the first to produce a given organization, and
desiring to patent it, may see at once a patentable variation on the
device. In other words, he makes two machines patentably different,
but both embodying his main invention. He drafts his broad patent
claim to cover both machines. In his patent he must illustrate his
invention, and he accordingly shows in the drawings the preferred
machine. The two machines represent two species of his generi