870 FEDEEAIi EBPOBTBB. �ented combination and the device of the defendant, which it is admitted he has used, both of which have been before us, we cannot doubt that they are substantially the same. The differences, so far as they exist, are merely formai. The funetion performed by each device is the. same; the mode of performance is substantially the same in each, and the ele- ments of the combination are found in each. Those elements are four. Bach has a flask to contain material for a blaat, and each flask has a cover. It is immaterial how the cover is attached to the body. The mode of attachment con- stitutes no part of what the patentee claims, nor does the shape of the cover. Both devices plainly have reference to a tor- pedo to be set vertically, and to be fired by a weight dropped from above. The patentee has a priming ehamber entered through the cover. The priming ehamber is a small apart- meut entered through the cover, intended to contain a charge to be fired into the body of the flask, Of what material the ehamber shall be made is not made essential or speciûed. �The defendant's device has three priming chambers entered through the cover of the flask, or plate or disk, which consti- tutes the cover, Through this cover three perforations are made, extending into the interior of the flask, and a Smith & Wesson pistol cartridge is forced into each, It is needless to say, what is too obvions to need any remark, that the copper case of the cartridge, fiUed as it is with powder to be ex- ploded by a fulminate in the vein, is a priming ehamber answering ail the purposes of that in the Eoberts patent, and a clear equivalent for it; and the buUet which confines the powder in the copper case is a plug answering ail the pur- poses of the plug in the complainant's device. �The remaining element of the patentee's device is the nip- ple. The funetion of the nipple is twofold : to hold the cap in position over the pi-iming ciiamber, and to supply an anvil upon which the fulminate in the cap may be exploded into the ehamber by the falling of the weight. There is no nip- ple in form in the defendant's apparatus, but there is a clear equivalent, performing the same functions, and in substan- tially the same manner. The perforation holds the cap ia ����
