Opinion of the Court. "69. And then heat it? "A. Yes. "70. And then extract the oil by pressure in the presses? "A. Yes; some of it; all that we did extract. "71. Are not those the same steps in the process of making oil that you used on the 2d of June, and ever since? "A. That is the process to-day." From this statement it is apparent that the beneficial result is due, not only to a proper degree of crushing of the seed in the rolls, but to a proper and uniform moistening of the crushed material in the heating machine before it is subjected to pressure. The question is, whether the patent sufficiently describes the operation to be performed in order to accomplish these results. After a careful consideration of the specification of the patent, and in view of the principle of law, that it is to be construed in the light of that knowledge which existed in the art at the time of its date, we are satisfied that it does sufficiently describe the process to be followed. Every step of this process was already understood, although not connected in the manner pointed out in the patent. The following things were known and used before the granting of the patent, to wit: First, the crushing of the seed between powerful revolving rollers, fed thereto by a supply-tube and feeding-roller, so as to pass in a sheet of uniform thickness between the rollers. Secondly, the moistening, mixing and heating of the crushed mass by means of steam and water in a mixing machine. Thirdly, the pressure of the material thus prepared, in moulds, by means of hydraulic power. These several steps being well known in the art when the patent was applied for, required no particular explanation. The patentee had only to say to the oil manufacturers of the country what he did say, namely: Crush your seed evenly and sufficiently between powerful rollers as heretofore; and, then, instead of passing it under the muller-stones, as you have heretofore done, transfer it immediately to the well known steam-mixing machine, and moisten and mix it equably and sufficiently for pressing. Every oil manufacturer in the country would understand him. They Opinion of the Court. would also understand that it might require additional care and skill to make the new process work successfully. It is evident that they did understand him, and that the manufac ture of linseed oil, and oil-cakes, has ever since been greatly improved and facilitated by the invention. But whilst we are satisfied that the invention is that of a process, it is nevertheless limited by the clear terms of the specification, at least so far as the crushing of the seed is concerned, to the use of the kind of instrumentality described, namely, in the first part of the process, to the use of powerful revolving rollers for crushing the seed between them under pressure. The claim cannot have the broad generality which its terms, taken literally, might, at first sight, seem to imply. But limited as suggested, it seems to us sustainable in law. It is true that the description also calls for the use of a vertical supply-tube and feeding roller. The latter is probably essential as a means of distributing the flow of the seed in a sheet of even thickness to the rolls. But the vertical supplytube is evidently an incidental arrangement, suited to one position of the rollers, namely, where a pair of rollers are set side by side. Where they form a pile, on top of one another, a vertical tube would be inapplicable. In such case the equivalent would be a slanting tube, or inclined plane. The vertical tube is clearly not an essential part of the instrumentality used, and constitutes no limitation of the process. The appellees also contend that they do not (in the words of the claim) "moisten the seeds by direct subjection to steam." It is proven, however, that they do moisten the seeds by a shower of spray in the mixing machine, produced by directing a jet of steam against a small stream of water. This is within the claim of the patent. The specification describes the process of moistening the seeds as follows: "they are then passed [after being crushed] directly, without the aid of muller-stones, to the mixing machine to be stirred, moistened, and heated by the admission of small jets of water or steam to the mass.' Again: "the crushed seeds are next placed in a steamjacketed reservoir of the mixing machine, where they are stirred, moistened, and heated by perforated revolving stirrer Opinion of the Court. arms which throw jets of water or steam into the mass," &c. Then the claim is for three successive steps, viz. the crushing of the seeds under pressure, the moistening of the seeds by direct subjection to steam, and the expression of the oil by suitable pressure. These words are to be read in the light of the explanations in the descriptive part; and thus read, it is apparent that the meaning of the claim is, that the crushed seeds are to be moistened and heated by the use of steam, or steam and water, immediately after coming from the rollers, without any aid from muller-stones. This is precisely what the appellees do. One of the defences set up is, an implied license. It seems that Lawther has another patent for some improvement in the stack of rollers now commonly used for crushing the seed, and supplies them to order through a foundryman by the name of McDonald. The appellees purchased a set of these rollers from McDonald with the knowledge and consent of Lawther. These rollers were returned on account of some imperfection in the material; but the frame was retained, and the appellees procured similar rollers made elsewhere. They contend that by this transaction Lawther gave his consent to their use of his process. We do not think that there is sufficient evidence of any such consent. The use of the rollers did not necessarily involve the use of the process, and there is no proof that anything was said about the process. Other points were raised which we do not deem it necessary to discuss. We cannot but think that Lawther discovered a new process of manufacturing oil from seeds, and that he was entitled to a patent therefor; and we are of opinion that the patent in suit, construed as we have suggested, is a good and valid patent. We are also of opinion that the appellees infringe the patent, and that they have not shown any legal defence to the suit. It follows that the appellant is entitled to a decree for an injunction and an account of profits and damages, as prayed in the bill. The decree of the Circuit Court is, therefore, reversed, and the cause remanded with instructions to enter a decree for the appellant, and take such further proceedings as may be in conformity with this opinion. Opinion of the Court. HUMISTON v. WOOD. ERROR TO THE CIRCUIT COURT OF THE UNITED STATES FOR THE EASTERN DISTRICT OF PENNSYLVANIA. Argued November 29, 1887.- Decided January 9, 1888. In its opinion this court reviews the evidence offered by the plaintiff on the trial of the case in the court below, none being offered there by the defendants, and finds it sufficient to entitle the plaintiff to have the issue submitted to the jury; and as the court below directed the jury to find a verdict for the defendants, which was done, and a judgment was entered on the verdict, this court reverses the judgment and remands the cause, with directions to grant a new trial. ASSUMPSIT. Plea: Non assumpsit. Verdict for defendant, and judgment on the verdict. Plaintiff sued out this writ of error. The case is stated in the opinion of the court. Mr. Francis E. Brewster and Mr. F. Carroll Brewster for plaintiff in error. Mr. David W. Sellers was with them on the brief. Mr. Wayne Mec Veagh for defendants in error. Mr. A. H. Wintersteen was with him on the brief. MR. JUSTICE MATTHEWS delivered the opinion of the court. This is an action of assumpsit brought by the plaintiff in error to recover the sum of $25,000 as consideration for the sale and transfer to the defendants below of the exclusive right for the States of Pennsylvania and New Jersey to make, use, and vend to others "Humiston's Atmospheric Hydrocarbon Apparatus" for generating light and heat, under letterspatent dated June 24, 1879, No. 216,853, issued to Ransom F. Humiston. The defence relied upon was the plea of non-assumpsit. The cause was tried to a jury, and the testimony having closed on the part of the plaintiff, the defendants offering none, the judge charged the jury to return a verdict for the defendants, Opinion of the Court. which was accordingly done. This ruling being duly excepted to, is now assigned for error, all the evidence in the cause being brought into the record by a bill of exceptions. The principal witness on the part of the plaintiff below was Ransom F. Humiston, the patentee. He testified that, having received his patent on June 24, 1879, he was introduced to the defendants on the 2d of July by their superintendent, they being manufacturers of ranges and heaters. Having tried and tested the patented apparatus at their manufactory, a negotiation was entered into for the sale of the patent. In answer to the question how he proposed to sell it, the witness stated that he had no experience, but understood that the usual way was to form a stock company, and that if he did not find a purchaser he should organize one. One of the defendants asked him if he was particular about forming a stock company, and whether he would be willing to sell it to the firm. He said he would prefer to do this, and named $20,000 as the price for Pennsylvania, $5000 cash and $5000 in monthly instalments. After some further conversation, the defendant said that it would be easier to raise the money by forming a stock company, and went to the office of an attorney for the purpose of having the papers drawn to contain their agreement. At this time it was further agreed to include New Jersey at an additional price of $5000 on the same terms. The interview at the attorney's office when the papers were drawn was on July 31, 1879, and they were signed on the 2d ,of August. The witness added: "The substance of what was said by defendants was, that we will be the owners of the patent, but it is necessary to have certain names to an application for a charter, and we (myself, Myers, and Feltwell) consented to go on application articles." The papers referred to by the witness and put in evidence are two. The first is an agreement concluded July 31, 1879, the parties to which are Joseph Wood, James P. Wood, B. M. Feltwell, William H. Myers, and R. F. Humiston. It was thereby agreed that the parties named would "associate themselves together for the object of obtaining a charter of incorporation under the name and title of the American Light and Heat Company of |