CHAPTER V.

QUESTIONS OF LAW AND QUESTIONS OF FACT.

§ 379. THE several provinces of the Court and the jury, in the trial of patent causes, have already been incidentally alluded to, but it may be proper to give here a summary of the principal questions which constitute matters of fact and matters of law.

§ 380. The question of novelty is a question of fact for the jury. It embraces the two questions, of whether the plaintiff, or patentee, was the inventor of the thing patented, and whether the thing patented is substantially different from any thing before known. These are questions of fact for the jury, upon the evidence. But it is for the Court to instruct the jury what constitutes novelty, in the sense of the Patent Law, as well as what amounts to a sufficiency of invention to support a patent. So, also, the question of prior public use is a question of fact.2

§ 381. The question, whether the renewed patent is for the same invention as the original patent, is also a question of fact for the jury; 3 as is likewise the question, whether the invention has been abandoned to the public.*

1 Whittemore v. Cutter, 1 Gallis. 478: Lowell v. Lewis, 1 Mas.; Carver v. Braintree Manuf. Co. 2 Story's R. 432, 441.

2 Ante, § 53, note 3.

3 Carver v. Braintree Manuf. Co. 2 Story's R. 432, 441.

4 Ante, § 57, note 2.

§ 382. The question of utility is a question of fact, under some circumstances, and, under other circumstances, it may be for the Court, without referring it to the jury, to pronounce the patent void. We have seen that a "useful invention," in the sense of our law, is one not injurious or mischievous to society, and not frivolous or insignificant, but capable of use, for a purpose from which some advantage can be derived; and that, when an invention is useful in this sense, the degree or extent of its usefulness is wholly unimportant. There are, therefore, two modes, in which the utility of an invention may be impeached; first, when it appears, on the face of the letters-patent and specification, that the invention is injurious to the morals or health of society; secondly, when it appears, on the evidence, that the thing invented, although its object may be innocent or useful, is not capable of being used to effect the object proposed.

§383. The question, whether the invention is useful, in the first sense, is a question whether the patent is void, on the face of it, as being against public policy; or, in other words, because the subject-matter disclosed by the patent is not a patentable subject. This is a question of law for the Court. But when it does not appear that the invention has any noxious or mischievous tendency, but, on the contrary, that its object is innocent or salutary, there may be a farther question, whether the means, by which the inventor professes to accomplish that object, will, in practice, succeed or fail. It is not essential to the validity of a patent, that the success of the means made use of should be complete, or that the thing invented should supersede any thing else used for the same purpose; because the law looks only to the fact that the invention is capable of some use. Thus,

1 Langdon v. De Groot, Paine's C. C. R. 203; Lowell v. Lewis, 1 Mason, 182; Phillips on Patents, p. 432.

if a machine is useful for some of the cases for which it is intended, although cases may occur in which it does not answer, it is still useful, in this sense of the Patent Law;1 but if any thing claimed as an essential part of the invention is useless altogether, the patent is invalid, because there is a total failure in point of usefulness.2 These questions, whether the invention is capable of use, for the purpose for which it is claimed, and whether any thing claimed as essential is entirely useless, depend upon evidence, and are questions of fact for the jury.3

§ 384. In like manner, the question whether an invention is frivolous or insignificant, is a question of law. If the object proposed to be accomplished is a frivolous or insignificant object, from which no advantage can be derived to the public, it is for the Court to pronounce the patent void, as not being for a patentable subject. But if the object proposed is not clearly frivolous and unimportant, but the means by which it is proposed to be accomplished do not succeed in producing the result, the question returns to the usefulness of the means, and this again becomes a question of fact for the jury.

§ 385. The construction of the specification, as to the extent of the claim, belongs to the province of the Court. The Court must determine, upon the whole instrument, what the claim actually covers, and whether the patent is valid in point of law. The jury are, therefore, to take the construction of the patent, as to the extent of the claim, from the Court, and to determine whether any thing that is included in the claim is not new. But if the specification

1 Haworth v. Hardcastle, Webs. Pat. Cas. 480.

2 Lewis v. Marling, Webs. Pat. Cas. 490, 495.

3 Haworth v. Hardcastle, ut supra; Lewis v. Marling, ut supra; Hill v. Thompson, 3 Meriv. 630, 632; Lowell v. Lewis, 1 Mason, 182; Bedford v. Hunt, Ibid. 302.

contains terms of art, which require explanation, by means of evidence, it is for the jury to find the meaning of those terms.1

§ 386. And, here, it is very important to ascertain whether there are any principles, which are to guide the Court in construing patents, peculiar to these instruments, or whether they are to be construed, in all respects, like other written instruments, and without the aid of extrinsic evidence. In one sense, a patent is a deed, being a grant of the government, under seal; the letters-patent, the specification, and the drawings annexed, being taken together as one instrument. But it often happens, that the extent of the claim is not manifest on the face of the specification itself. The question arises, therefore, how is the Court to ascertain the precise extent of the claim, as matter of law? The specification is a written instrument, in which the patentee has undertaken to state the invention which he professes to have made, and for which he has obtained letters-patent. In determining the real extent of the claim thus made, it is obvious, that the actual invention of the party is a necessary auxiliary to the construction of the language which he has employed in describing it. The thing of which the patentee was the real inventor, is what he was entitled to claim, and the question, in all cases requiring construction, will be, whether he has claimed more or less than that thing, or exactly what that thing is. If he has claimed more than his actual invention, that is, more than that of which he was an original and the first inventor, his claim is inoperative, under our law, pro tanto. If he has claimed less, his exclusive right is restricted to what he has claimed. If he has claimed the just extent of his actual invention, he is entitled to hold it, in all its length and breadth.

§ 387. There are two sources to which the Court is enti

1 Ante, § 123, 124.

.

tled to resort, in construing a claim. In the first place, resort may be had to the descriptive parts of the specification, where the patentee has undertaken to state what his invention is; in other words, the Court is to inquire what the patentee has said that he had invented. If his statement or description of the invention is clear and explicit, then the language in which he has made his claim, which is generally to be found in a summary statement of the subjectmatter for which he asks a patent, may and should be construed so as to include the actual invention previously set forth, if it can be so construed without violation of principle; for the general maxim, under which the construction is to be pursued, is, according to the spirit of the modern authorities, ut res magis valeat quam pereat.

§ 388. But it may be uncertain, upon the terms of the descriptive parts of the specification, if unaided by evidence, what the precise extent of the invention was; and this may happen, without that degree and kind of ambiguity which renders a patent void for uncertainty, or because the directions could not be carried out by a competent workman. For instance, the patentee may state that he employs something which turns out not to be new; and the question will then be, whether he has so described that thing as to claim it as part of his invention;- or his invention may be so stated,

1 See Russell v. Cowley, Webs. Pat. Cas. 469, 470; Davoll v. Brown, 1 Woodbury & M. 53, 59. Where the construction depends, as it generally does, in the first instance, on the terms of the specification, the preamble may sometimes be resorted to. Winans v. Boston & Providence Railroad, 2 Story's R. 412. Sometimes the body of the specification. Russell v. Cowley, ut supra, 459, 463. Sometimes the summing up. Moody v. Fiske, 2 Mason, 112, 118. Generally, the whole is examined together, unless the summary seems explicitly to exclude the rest of the specification, and to require a construction by itself alone. McFarlane v. Price, Webs. Pat. Cas. 74; 1 Starkie, 199; The King v. Cutler, Webs. 76, note; 1 Starkie, 354; Ames v. Howard, 1 Sumner, 482, 485. See Davoll v. Brown, ut supra.