38 » r rnnman. nmroarmn.
primary examiner, February'24, 1880, and held that Lockwood was
entitled to the honor of the invention. The commissioner of patents,
—the last judgment being appealed from,—on May 3, 1880, decided
that Holton was the original inventor, but refused to grant the letters
applied for, on the ground that the invention had been in public use
more than two years prior to his application. An appeal being taken
to the supreme court of the District of Columbia, this last decision
was reversed. On September 28, 1880, the court held that Holton
was entitled to his letters patent. They were accordingly issued to
Orestes Cleveland, as his assignee, October 19, 1880, and numbered
233,511. This bill was filed by Lockwood on November 2d follow-
ing, to have the last-recited letters patent declared void. Cleveland
has answered, denying all the material allegations of the bill of com-
plaint, setting up that Holton was the original and Erst inventor of
the improvement claimed in the two patents, and praying that the
letters patent issued to Lockwood, September 7, 1875, may be ad-
judged and declared invalid and void. With the answer, he also filed a
cross-bill, asking that the complainant’s patent might be held void,
and that he might be restrained from bringing an action in any court for
an infringement of the same. The cross-bill was subsequently dis-
missed by the court, upon the ground that section 4918 of the Revised
Statutes afforded all the relief in the original suit which the defend-
ant could possibly have in the cross·suit. See Lockwood v. Cleare-
lemd, 6 FED. Bar. 721. V
The case has been heard upon bill, answer, and proof, and presents
two questions for consideration: (1) Whether Lockwood, or Holton,
the assignor of the defendant Cleveland, was the prior inventor of A
the improvement claimed in the letters patent; and (2) whether there
was such prior use of the invention as to render the patent of the
first inventor void. { ° ,
An examination of the specifications and claims of the two patents
` shows that they are for the same invention, to-wit, a rubber eraser,
as a new article of manufacture, having soft-finished erasive sur-
faces. The objection to the rubber ordinarily in use before the spring
of 1875, for erasive purposes, was that the outer surface was covered
with a glaze, produced in the process of vulcanization, and which
hindered the rubber from taking hold of and removing pencil marks
from paper without smirching the latter. In order to prepare the ’
rubber for immediate use as an eraser, this glaze or crust was fre-
_ quenzly got rid of by paring off the surface of the rubber with a knife
or other sharp instrument.
The complainant says that some time before 1870 he learned that
the surface of vulcanized rubber became soft and velvety by long-
continued drumming, and it at once occurred to him that this was
the proper mode of preparing it for erasive purposes. But although
he made many experiments, chiefly in the mixture of different ingre-
dients with varying proportions to discover the best combination for