Ligowsky is able to show that in 1887 he conceived the improvements here in controversy and actually gave such substantial expression to the invention as that without the further exercise of the inventive faculty one familiar with the construction and operation of the old type of machine could construct a new machine embodying the novel features, it must follow, if the case be determined upon the assumption of the truth of Ligowsky's account of the matter, that he made a full disclosure of his invention to Hisey, and that the latter is not entitled to the attitude of one whose conception is later, but who first constructed an organized machine and first applied for a patent. In other words, if Ligowsky ever invented the improvements involved, he did so in 1887, and disclosed his conception the same year to Hisey. If, in fact, Ligowsky had in 1887 such a full and adequate conception of this invention, and disclosed it to Hisey, the question as to whether he used reasonable diligence in perfecting his drawings or building a machine or applying for a patent is a matter of no importance as the matter now stands on this bill. Hisey's case must stand or fall upon the question as to whether he is the sole and first inventor. If, in fact, he has only appropriated the conception of Ligowsky, it is of no moment that he made the first machine or filed the first application for a patent. Ligowsky's neglect to push his conception to completion at an earlier date or file an application more promptly is of no avail to the complainants if Hisey derived his knowledge of the improvements here involved from Ligowsky.

Upon the proceedings in the Patent Office priority of application operated most favorably for Hisey. The burden was thereby thrown upon Ligowsky to show one of two things-either that Hisey had never at any time made the invention he claimed or that his own conception antedated that of Hisey, and thus entitled him to carry back the question of priority to the date of first conception. That burden is now, by reason of the action of the Patent Office, shifted, and it now devolves upon the assignee of Hisey to show that in point of fact Hisey's conception antedated that of Ligowsky or that the latter never at any time made the discovery in controversy. For the purpose of this branch of the case we shall assume that Ligowsky disclosed to Hisey during 1887 all that he had done or conceived about the construction of a cartridgeloading machine embodying an endless-belt carrier. If Ligowsky's conception was at that time sufficiently developed and perfected to enable one familiar with the construction and operation of the old type of machine to construct a cartridge-loading machine embodying the novel features described in the interference issues by the exercise of mechanical skill and without further invention, he, and he alone, is the first inventor, and Hisey is merely attempting to appropriate the conception of Ligowsky. On the other hand, if Ligowsky had only an inchoate idea that in some way an endless-belt carrier, suitably actu ated, might be devised, which could be substituted for the old rigid circular carrier, but did nothing toward developing and demonstrating 15377-18

the utility of his conception, he would not be an inventor at all. The mere existence of an intellectual notion that a certain thing could be done, and, if done, might be of practical utility, does not furnish a basis for a patent or estop others from developing practically the same idea. (Agawam Co. v. Jordan, 7 Wall., 583–602; Christie v. Seybold, C. D., 1893, 515; 64 O. G., 1650; 6 U. S. A., 544.)

So if ineffectual efforts were made to give the idea form, through drawings, models, or machines, but were abandoned before reaching such a stage of completion as to require only ordinary mechanical skill to carry the conception to success, the claim of priority of invention could not be sustained against a later independent conception carried into practical form at an earlier date. (Reed v. Cutter, Fed. Cas., No. 11,645.)

The solution of the contention of complainant's counsel now under consideration must depend upon the answer to the question we now reach, which is this: Did Ligowsky in 1887 have such a complete and adequate conception of this invention as to enable a skilled mechanic familiar with the construction and operation of the old-type machine to construct a machine embodying the novel features of this controversy from the description he disclosed to Hisey and others without further invention? All that Hisey did and said during that year is competent evidence to show how far he had then developed his idea and what he then claimed to be his invention. Whatever he said as to the nature of his invention, mode of operation, etc., is competent upon the question as to the sufficiency of his prior conception to enable him to carry back his later construction or later application to the time of his first conception.

It was said by this Court in Christie v. Seybold, heretofore citedthat the man who first reduces an invention to practice is prima facie the first and true inventor, but that the man who first conceives and, in a mental sense, first invents a machine, art, or composition of matter may date his patentable invention back to the time of its conception, if he connects the conception with its reduction to practice by reasonable diligence on his part, so that they are substantially one continuous act. The burden is on the second reducer to practice to show the prior conception, and to establish the connection between that conception and his reduction to practice by proof of due diligence.

That burden may be met by the exhibition of drawings and by oral explanations of his conception antedating the first reduction to practice by another. (P. & T. R. R. Co. v. Stimpson, 14 Pet., 448; Reed v. Cutter, cited above; McCormick Machine Co. v. Minneapolis Harvester Works, C. D., 1890, 336; 51 O. G., 1130; 42 Fed. Rep., 152.)

That Ligowsky did not construct a machine during 1887 or at any other time is not vital to this question. It was said in Webster Loom Co. v. Higgins, by Justice Bradley, (C. D., 1882, 285; 21 O. G., 2031; 105 U. S., 594,) that

an invention relating to machinery may be exhibited either in a drawing or in a model so as to lay the foundation of a claim of priority, if it be sufficiently plain to enable those skilled in the art to understand it.

In McCormick Machine Co. v. Minneapolis Harvester Machine Co. (C. D., 1890, 336; 51 O. G., 1130; 42 Fed. Rep., 152) a question of priority of invention was settled upon proof of oral explanations of certain improvements touching harvesting-machines made by the inventor in the presence of an old machine, the inventor orally explaining the scope of his proposed improvement and how he proposed to apply it in terms sufficiently clear to enable a good mechanic familiar with such machines to construct the device from the description given.

That Ligowsky had such an adequate conception of his invention in 1887 and made such full disclosure, through his drawings and by oral explanations, sometimes by aid of his sketches and sometimes in the very presence of the old Peters machines, as to enable persons skilled in such machines to have constructed and applied his improvements without further exercise of the inventive faculty was one of the facts found in favor of Ligowsky in the interference proceedings by the Examiner of Interferences. Upon appeal the Board of Examiners-in-Chief were of a contrary opinion; but on final appeal to the Commissioner in person the decision of the Examiner of Interferences was affirmed, the Commissioner distinctly deciding that—

Ligowsky's sketches show the endless-band mechanism for giving it intermittent motion and a suitable shell delivery. They therefore [said the Commissioner] disclose the improvement in controversy sufficiently to entitle him to properly claim that he had a conception of that invention in 1887.

These differing conclusions of the several Boards of the Patent Office who heard the evidence submitted upon this vital question of the adequacy of Ligowsky's conception of this invention in 1887 clearly indicate that the question was one not free from doubt, although the final conclusion was favorable to Ligowsky. Some evidence has been submitted upon this question which was not before the Commissioner. It consists principally in expert opinion and criticism of Ligowsky's sketch drawings and of the drawings and specifications attached to Ligowsky's application for a patent. These seven original sketches are undoubtedly rude and imperfect and do not show or attempt to show an organized working machine; but we do not regard this as a vital defect. The claims put in interference do not involve anything more than certain improvements upon machines well known in the art and contemplate a combination of certain novel features with the loading-tools and other devices of the old Peters machine. The question as to whether these sketches so clearly show the novel features as that one familiar with the construction and operation of the Peters machine could from these construct a machine embodying the endless-belt feature is one addressed to persons possessing a mass of information about the old art. If such persons from these sketches could construct a machine containing the improvements conceived by Ligowsky without the further exercise of the inventive faculty, then it is very clear that Ligowsky must be held to have had a sufficient conception in 1887 to entitle him, on a question of priority, to carry the date of his invention back to the date of these

drawings. That they are incomprehensible to one unacquainted with such machinery or to a mechanic unaware of what they purported to be is no answer. That they do not in all respects show the relation of the novel features to the old loading-tools, nor describe precisely the mode of attachment, nor with scientific exactness show other details of the combination is not fatal if the absent features are such as would be readily supplied by a mechanic familiar with the subject and without requiring further invention. The well-known statement of the doctrine touching the sufficiency of description in the specifications and drawings of an application for a patentable novelty by Justice Bradley in Webster Loom Co. v. Higgins (C. D., 1882, 285; 21 O. G., 2031; 105 U. S., 586) applies with even greater force to the adequacy of such sketch drawings when the question is one of carrying back the date of an invention to the time of first conception. In the case referred to, Justice Bradley, for the Court, said:

If a mechanical engineer invents an improvement on any of the appendages of a steam-engine, such as the valve-gear, the condenser, the steam-chest, the walkingbeam, the parallel motion, or what not, he is not obliged, in order to make himself understood, to describe the engine, nor the particular appendage to which the improvement refers, nor its mode of connection with the principal machine. These are already familiar to others skilled in that kind of machinery. He may begin at the point where his invention begins, and describe what he has made that is new, and what it replaces of the old. That which is common and well known is as if it were written out in the patent and delineated in the drawings.

The seven drawings made by Ligowsky are not a connected series. Neither do they or any one of them delineate a fully-organized machine. Some of them represent one feature and some another, and all show that they were experimental in character and indicate but roughly the progress of the idea in the inventor's mind. We here set them out, prefacing that the one appearing to be No. 6 is the first made in order of time.

The explanations and notes found on them were generally contemporaneous with the sketch and are to be taken as constituting evidence as to the state of the conception in the inventor's mind at the time. The explanation made by Ligowsky of these drawings on the interference proceeding was as follows:

Q. 25. Please look at sketch No. 1, and state what it is intended to represent.— A. Sketch No. 1 shows a double endless leather belt, with a centrally-inserted thin metal steel band, riveted together with copper rivets. Upon the outer face of this belt are mounted metallic shell cases or carriers, whose bore coincide with a hole cut in said endless belt, so as to allow the empty shells to be inserted. On said drawing I observe notes written in my handwriting, explaining the details and manner of making such a belt. The first note reads: "Shell-case to be turned thin at base, and crimped under into the belt, and which will cause same to conform with face of pulleys." Second quotation: "Endless double belt with metallic-strip center." Last note reads: "Make base wider for holding rivet." This referred to a method of stiffening the shell-case on the belt.

Q. 26. State when these notes quoted in your last answer were put on the drawing.-A. My recollection is that these notes were added to the drawing a day or two after it was made. There was some difficulty in securing this case firmly on the

leather, and various ideas occurred to me, but the crimping under of the thin end of the case prevailed with me and in order not to have it slip my memory I made a note of same upon the drawing.

Q. 27. Please look at sketch No. 2 and describe what it is intended to represent.A. Sketch No. 2 shows a pulley for driving an endless belt in combination with an actuating device. This actuating device consists of a can-nosed link and hook, which was to be driven from above by an eccentric or cam wheel, which would impart a reciprocating motion to the same to the link. The operation of this link,

which was pendent from a knee-joint, shown just below the word "Top," and above the red line of the sketch, is as follows: The link in its downward stroke comes in contact with a pin and roller mounted in the spokes of the pulley, engaging itself with the pin and roller by sliding along on same until the portion of the link representing the barb or hook of the link is reached, whereupon being pendent it drops into engagement by its own weight.

(There is a note on here which I will read, "Pulley with lifting device for an endless belt.")