nSOCTOB' V. BBlià.- 417 �that this pin îs stationary, Bo that when the poîe îs unshackled the lower part remains in position; and, as described by Dr. Cresson, the slot in the brac& may be run upon the bottom of it, and thus held up steadily, in a horizontal position, while Ihe pin is being run through. In the same way it may be held thas steady while the pin is being withdrawn and the pôle unshackled. �The plaintiff, charging the defendants with infringement of his rights under the paient, bas brought this suit to recover compensation for the injury which he says bas thus been inflicted. That the defendants manufaetured cars and pôles, nsing the plaintiff's devices substantiaUy for coupling and Bupporting the pôle, is shown by the testimony, and is not denied. The number of cars and pôles to which the devices were so applied is stated to be from 62 to 87 in number. If the case rested here the plaintiff would be entitled to recover. Your verdict, however, in such case, would be for nominal damages only, consisting of six cents, for you would thus have nothing by which to determine that more had been sustained. �The plaintiff, however, bas undertaken to satisfy you that he had an established royalty, or license fee, for the use of his patent; which fee hetestified is $50 for the devices cov- ered by the two claims. If you find that he had such estab- lished general license fee, — that is to say, that he charged and was paid, not in a single instance, but generally, such sum as he states, per car, for the use of his invention, — this would afford a standard or guide -frhereby the extent of his injury from the defendants' use might be ascertained and measured, in case the patent were found to be valid as respects both the claims before stated. And in such case it would justify you in rendering a verdict in his favor for a sum equal to |50 for each of the several cars and pôles manufaetured by the de- fendants with the plaintiff's devices for shackling and support- ing the pôle. For, while the defendants did not themselves use the car and pôle with a device thus upon it, their act of selling the car and pôle so manufaetured for use by others, would, under the circumstances stated, render them responsi- ble for the use. The plaintiff further testifies that he had a �v.4,no.5 — 27 ����
