9Û§ ffEDEEAL EBPOETBB. �one oannot exîst without the other, the existence of the one may be presumed on proof of the existence of the other. Where the utility is proved to exist in any degree, a sufficiency of invention to support the patent must be presumed. We do not say the single fact that a device has gone into general use, and bas displaced other devices which had previoiisly been employed for analogous uses, establishes in ail cases that the later device involves a patentableinvention. It may, however, always be considered; and, when the other facts in the case leave the question in doubt, it is suffieient to turn the scale." �So in Eppinger v. Riche y, le Blatchf. 307, Judge Shipman said: "Two facts exist in this case: one is that an impor- tant improvement bas been attained; the second is that the improvement is in a staple article which bas been manufac- tured in this country for a long series of years. * * * The utility pf the patented article bas been evinced by its largesales.
- * The inventer evidently gave tp the public an article
which: it wanted, and which it had not previously known. Without giving to the general use of the invention as a test of its patentability any greater importance than the supreme court in the case of Smith v. Goodyear Dental Vulcanite Co. (above quoted) indicate sbould be given to this circumstance, I am of the opinion that the facts in the case fully establish the conclusions : (1) That however simple the change in the method of manufacture apparently may bave been.yet it was a change which required invention for its accomplishment ; and (2) that the improvement resulting from the cbanged method of manufacture bas been so great that the article which is produeed is, within the meaning of the patent aots, a new and useful article of manufacture." �Mr. Justice Shepley said, in the case of Isaacs v. Ahrams, 14 0. G. 862 : "A change in the form of a machine or instru- ment, thougb slight, if it works a successful resuit, not before accomplished in a similar way, in the art to which it is ap- plied, or in any other, is patentable." �Judge Shipman said, in Stanley Works v. Sargent, 8 Blatchf. 346: "Utility is not an infallible test of originality. The patent law requircs a thing to bo new as well as useful in ����
