36 HARVARD LAW REVIEW. of a machine ; and the patentee can control only embodiments of the claim, with a fair and proper reservation of equivalents for accomplishing the result at which his invention is aimed When, therefore, a patentee sues for infringement of his rights, one of the main questions for solution is whether the defendant has accomplished substantially the same result as that contem- plated by the patentee, in and by substantially the same means as are specified by the patent claim. If the defendant has accom- plished the useful result by using all of the component elements of the claim, he is an infringer; but if, on the other hand, he has managed without one or more of those components or their sub- stantial equivalents, he escapes the charge ; for the claim is read as an integer.^ Broadly speaking, the manufacture, sale, or use of an element of the combination, or of any number of elements in combination short of the complete whole recited in the claim, is innocent. This rule was invoked for the defendant in the leading case of Wallace v. Holmes,^ where the facts stood thus : — The complainant patentee had a patent for an improved burner in combination with a peculiar chimney, in a lamp ; the defendants manufactured and sold the burner, leaving the purchasers to supply the chimney, without which the burner was useless. The lamps in the hands of purchasers from the defendants became complete infringements of the patent claim. " And now it is urged that, having made and sold burners only, they are not infringers, even though they have distributed them throughout the country in competition with the complainants, and have, to their utmost ability, occupied the market, with the certain knowledge that such burners are to be used, as they only can be used, by the addition of a chimney.^ The italics in the foregoing quotation from Judge Woodruff's opinion are intended to emphasize that portion of the facts which is, it is submitted, the key to the situation. The defendants in 1 A combination claim does not cover the elements separately. Evans v. Eaton, Pet. C. C. 322. The whole combination is a unit. Watson v. Cunningham, 4 Fisher, 528; Rowell V. Lindsay, 10 Biss. 217; Schumacher v. Cornell, 6 Otto, 594; Gill z/. Wells, 22 Wallace, i. A claim is not infringed by use of less than the entire combination. Burdett v. Estey, 16 Blatch. 105 ; Sharp v. Tifft, 18 Blatch. 132 ; Fuller v. Yentzer, 94 U. S. 288 ; Reedy v. Scott, 23 Wall. 352. 2 9 Blatch. 65. ' Wallace v. Holmes, 9 Blatch. 74.
