L 'Patents—Suit fob Infbingement—Extent of Use of Device.

That the device of a patent was publicly used and exhibited in actual use for two years is sufficient to sustain a suit for infringement without a showing that it has been in constant use since that time.

[Ed. Note.—For cases in point, see vol. 38, Cent Dig. Patents, § 34.]

2. Same—Validity—Presumption From Grant.

Due consideration must always be given by the court or jury, as the case may be, to the presumption of 'validity arising from the grant of a patent and the real question in all cases is whether or not the evidence in the case is sufficient to overcome such presumption.

[Ed. Note.—For cases in point see vol. 38, Cent. Dig. Patents, §§ 162-165.]

3. Same—Construction of Claims—Generic Claims.

A pioneer inventor is entitled to a generic claim, and may also include specific claims in the same patent, and in such ease the broad claims are not, prima facie, to be restricted by reading into them the specific devices claimed in the narrower ones.

[Ed. Note.—For eases in point, see vol. 38, Cent Dig. Patents, §248.]

4. Same—Validity and Infringement—Regulator fob Mechanical Musical Instruments.

The Tremaine & Pain patent No. 552,796, for improvements in mechanical musical instruments using perforated music sheets, by which two such sheets in two separate organs or a bank organ, are made to move in unison, so that the instruments will play without variation in time, is valid, and embodies an invention of such novelty and importance as to constitute a distinct step in the progress of the art, and to entitle its claims to a broad and liberal construction. As so construed it is infringed by the device of the Fleming patent, No. 659,442, which, although differing in details, embodies and appropriates the essential principles of the earlier invention.