monopolies in general to be void; but at the same time excepting "letters patent and grants of privilege for the term of fourteen years, or under, hereafter to be made of the sale, working, or making of any manner of new manufactures within this realm, to the true and first inventor and inventors of such manufactures which others at the time of making such letters patent and grants shall not use," etc. (§ 6.) It is further declared "that the same shall be of such force as they should be if this act had never been made, and of none other." It is well settled that this statute did not create, but controlled the power of the Crown in the granting of patents. It has been distinctly held that patentees have always derived, and still derive, their rights, not from the statute, but from the grant of the Crown.2 In this country the power to grant patents is vested by the United States Constitution exclusively in Congress. The right is accordingly statutory as contrasted with that in England, which originates with the common law, but limited and confined by statutory restraints. The principles of law governing the general subject in the two countries are substantially the same. A patent may be defined to be an exclusive temporary privilege, obtained from governmental authority granted to an inventor or discoverer, or proprietor of an invention or discovery, for the manufacture, sale, and use of the article or thing to which the patent refers. The thing patented may be either a machine or a process. It is not easy to draw the line between the two. A leading distinction is, that in a machine, use is made of the mechanical powers; 1 Coke's Third Institute, Case 85, patent was granted to Mr. Matthey, a p. 181. cutler, at Fleetbridge, in the beginning of 2 Caldwell v. Van Vlissengen, 9 Hare, this queen's [Elizabeth] time, which I have 415, 427. There is strong reason to believe that the English courts would not, even before this statute, have upheld any grant of a patent for an invention which had already gone into public use. In other words, this cardinal rule of patent law was not derived from the Statute of James, but from judicial decision, since this would be a monopoly of the class justly termed "odious." The counsel in Darcy v. Allin, Noy's Reports, pp. 182, 183, cites three cases (one in the 9th of Queen Elizabeth, and all before the Statute of James), where the patent was judicially declared void, because the invention had already gone into public use before the issuing of the patent. One of his cases is worth transcribing. "A monopoly here in court to show, by which patent was granted unto him the sole making of knives with bone hafts and plates of lattin, because, as the patent suggested, he brought the first use thereof from beyond seas, yet nevertheless when the wardens of the company of cutlers did show before some of the counsel and some learned in the law that they did use to make knives before, though not with such hafts, that such a light difference of invention should be no cause to RESTRAIN them, whereupon he could never have benefit of this patent, although he labored very greatly therein." It would seem, from the use of the word "restrain" in this passage, that an injunc tion was resorted to at that early day. in a process, resort is had to chemical action. Important rules grow out of this distinction, which will be noticed more fully hereafter. A patent is in the nature of a monopoly, and in that aspect antagonistic to the interest of the public. It is to be tolerated only on the ground that it is legal, and the legislation authorizing it is only sound when under the circumstances the evils of a monopoly are as a rule overborne by the advantages to be derived from it. "An illegal monopoly is a public grievance," and it is for the interest of trade that the court should, on due application, so declare it.1 The subject of patents will be considered according to the following arrangement of topics. I. To whom the patent should be granted. II. The subject-matter of a patent. III. Proceedings in the Patent Office, to obtain a patent, to correct defects, to secure a reissue, and to determine questions of interference. IV. Substantive rights acquired under a patent: (1) The patent itself; (2) Derivative, or subordinate substantive rights, including renewal or extension, assignments, licenses, sale of single machines, etc.; (3) Infringement. V. Remedies: (1) When the patent is attacked: 1. By the United States; 2. By an individual; (2) Remedies by the patentee: 1. At law; 2. In equity. I. To whom the patent should be granted. The statute of 21 Jac. I., c. 3, § 6, confines the patent to the "true and first inventor." The law of this country confines the grant to an inventor or discoverer, the invention or discovery not being known or used by others in this country, and not patented or described in any printed publication in this or any foreign country, before his invention or discovery.2 The leading point of inquiry then is, who is an "inventor or discoverer" within the meaning of the statute. There may be two competing claimants for the patent, and the one who is the true and first inventor must be ascertained. The law protects him who was the first inventor, although he was not the first to adapt his invention to practical use, by permitting him to file a caveat. Independent of this caveat, the rule would have been that the person who first adapted his invention to practical use would be entitled to a patent.3 Until an invention is so perfected and adapted to use, it is not patentable. Accordingly, whoever finally perfects a machine, and renders it capable of useful operation, is entitled to a patent, though others may have had the idea, and made 1 The Queen v. Prosser, 11 Beav. 306, 317. A case of scire facias to repeal letters patent. 2 U. S. Rev. Stat. § 4886. Phelps v. Brown, 4 Blatch. 362. 4 Reed v. Cutter, 1 Story, 590; Lowell v. Lewis, 1 Mas. 182, 187. experiments towards putting it in practice. It will not be enough to take away the claim of first invention to show that suggestions aided the claimant. It must appear that they would furnish all the information necessary to accomplish the result.2 Nor will it invalidate a patent to show that every part of the machine described in it is not the original invention of the patentee; that is only necessary as to the parts claimed as his own invention.3 But the employment of mechanical skill to construct a machine in accordance with ideas furnished by another, gives no right to the invention. The amount of labor and expense to which a claimant has been put does not properly enter into the question of the right to the patent.5 A person is not deprived of his right to an invention made while in the service of another, unless his employment embraced the exercise of his inventive faculties. (a) Claim for a patent for improvements upon existing machines.It is a well-settled rule that there may be a patent for an improvement upon an existing machine, whether the latter be itself patented or not. In such a case, the inventor of the improvement must confine himself to a patent for that." So, if old materials and old principles be used in a state of combination, to produce a new result, there may be a patent. The invention consists in the combination, and the combiner is, for the purposes of a patent, the "first" inventor to that extent.8 A patentee may have a second patent for an improvement on the thing first patented. Under these rules it is not sufficient merely to place old parts in juxtaposition. There must be invention. This implies a new or peculiar function developed by the combination; all the elements must so enter in that each qualifies the others.10 Invention must be distinguished from mere mechanical skill. So, it has been held, that a combination of old elements is patentable where a new and useful result is produced by their 1 Washburn v. Gould, 3 Story, 122. See Cahoon v. Ring, 1 Cliff. 592. Ex parte Henry, L. R. 8 Ch. App. 167. 2 Pitts v. Hall, 2 Blatch. 229. Allen v. Rawson, 1 C. B. 551. 3 Holliday v. Rheem, 18 Pa. St. 465. 4 Yoder v. Mills, 25 Fed. R. 821. 5 Crane v. Price, 4 M. & G. 580. 353. 8 Hailes v. Van Wormer, 20 Wall. 9 Mathews v. Flower, 25 Fed. R. 830. 10 Pickering v. McCullough, 104 U. S. 310; contra, Stutz v. Armstrong, 20 Fed. R. 843. 11 Scott Mfg. Co. v. Sayre, 26 Fed. R. 153; Peard v. Johnson, 23 Id. 507; Atlan 6 Hapgood v. Hewitt, 11 Biss. 184. tic Works v. Brady, 107 U. S. 192; Aff'd, 119 U. S. 226. Beecher Mfg. Co. v. Atwater Mfg. Co., 7 Evans v. Eaton, 7 Wheat. 356; Whit- 114 U. S. 523. temore v. Cutter, 1 Gall. 478. (a) Cf. Solomons v. United States, 137 U. S. 342; Dalzell v. Dueber Mfg. Co., 149 U. S. 315; Lane & Bodley Co. v. Locke, 150 U. S. 193; Jencks v. Langdon joint action, or an old result in a cheaper or more advantageous manner.1 A patent for "improvements," -e. g., by the patentee, — is, to some extent, construed differently from an original patent, since a claimant in his specification may not only refer to the improvement which he now claims, but to former rights as something known, and only necessary to be referred to for the purpose of explaining the claim. This last matter is not to be construed with more strictness and precision than is necessary to enable it to fulfil that purpose of explanation for which it was introduced. Accordingly, where the patentee of the improvements had referred to electric currents transmitted through "metallic circuits," and a subsequent improvement (alleged to be an infringement) used "metallic circuits" in part, and the earth in part, it was decided that the expression "metallic circuits" meant metallic circuits "so far as it is material to the improvements claimed that they should be so;" and the defendants having used wholly metallic circuits in a respect material to the improvements of the plaintiff, they were held liable.2 This general subject will be more fully considered under the head, "The subject-matter of a patent." It is now necessary to notice the qualifications imposed by the statute upon the right to obtain a patent, whereby an application may be defeated notwithstanding patentability. Invention described in a printed publication, either here or in a foreign country. —A true first inventor or discoverer, so far as his own knowledge is concerned, may fail to obtain a patent, or, if he obtains it, may be defeated because the invention has been described in some printed publication before his own invention or discovery.3 If this fact appears, it is a good defence to an action for an infringement.4 Unless so described or patented, the inventor here is entitled to a patent, if he believed himself to be the first inventor.5 The rule is established in England that in order to invalidate a patent by a prior book publication, it is not enough to show that the invention was described in a published book, but it must also appear that it became known to a sufficient part of the "public." 1 Railway Reg. Mfg. Co. v. No. Hudson Co. R. R. Co., 26 Fed. R. 411; Davis v. Fredericks, 21 Blatch. 556. 5 O'Reilly v. Morse, 15 How. U. S. 62, 110; Hays v. Sulsor, 1 Fisher Pat. Cas. 532; Bartholomew v. Sawyer, 4 Blatch. 2 Telegraph Co. v. Brett, 10 C. B. 838, 347; Doyle v. Spaulding, 19 Fed. R. 744. • Plimpton v. Spiller, L. R. 6 Ch. D. 880, 881 (1851). 8 See U. S. Rev. Stats. § 4886. 4 Judson v. Cope, 1 Fisher Pat. Cas. 615. 412. The word "public" here seems to mean persons conversant with the particular subject, or persons who are desirous of taking out patents for new inventions, and therefore desirous of making themselves acquainted with the course of inventions generally.1 Under this principle it was held not to be sufficient that an American book of illustrations containing a drawing of the invention was on a book-shelf in the Patent Office, but not entered as a donation in the usual catalogue, though it appeared that the librarian saw it before the patent was taken out in England.2 It is enough, however, if known to the public, though not used.8 Invention first patented in a foreign country. — This is a ground for denying to an inventor here a patent, or defeating it if granted. This rule does not apply to the inventor or discoverer who obtained the foreign patent. He is entitled to a patent here under the terms of the Revised Statutes. The language of this section is: "No person shall be debarred from receiving a patent for his invention or discovery, nor shall any patent be declared invalid by reason of its having been first patented, or caused to be patented, in a foreign country, unless the same has been introduced into public use in the United States for more than two years prior to the application" for the patent here. The time must expire at the same time with that of the foreign patent, and must in no case exceed seventeen years. Invention known or used by others in this country. This fact will destroy the right of a claimant, without reference to the point whether the invention or discovery is described in any printed book. The knowledge or use may be proved as a fact.5 Invention or discovery suffered to go into public use by inventor or discoverer. This act is fatal to a patent if the public use be . suffered to exist for two years. (a) The same principle exists in England, but no definite time is fixed there. It is well settled that there must be no public use by the inventor or others with his consent prior to the grant of the patent." Some question may arise as to the meaning of the expression "public use" in this connection. It does not mean trials of an |