tives, and must not take away a right of property in existing patents.1

IV. PATENT OFFICE-1. Establishment.-The United States Patent Office is an office in the Department of the Interior, and is the place where all records, books, drawings, specifications and other papers relating to patents shall be safely kept and preserved. It must contain a library of such scientific works and periodicals, both American and foreign, as may aid the officers in the discharge of their duties. Various statutes provide for the distribution of copies of specifications and drawings of patents, for lithographing drawings and for reports.2

2. Officers. The officers of the Patent Office are a Commissioner, an Assistant Commissioner, three Examiners-in-Chief and Examiners.3 All officers of the Patent Office are incapable of acquiring or taking patents, except by descent, while employed in the office.

3. Duties of Commissioner.-The Commissioner of Patents, under the direction of the Secretary of the Interior, superintends and performs all duties respecting the granting and issue of patents directed by law.5

Bloomer v. Stolley, 5 McLean (U. S.) 158.

1. McClurg v. Kingsland, 1 How. (U. S.) 202; s. c., 2 Robb Pat. Cas. 145, The power of Congress to grant an extended or new term is plenary, and may be exercised by it in any way which may seem advantageous to it. Jordan v. Dobson, 4 Fish. Pat. Cas. 232; Blanchard 7. Haynes, 6 West. L. J. 82; Blanchard's Gun Stock etc. Factory v. Warner, 1 Blatchf. (U. S.) 258; Bloomer v. Stolley, 5 McLean (U. S.) 158; Evans v. Robinson, I Carolina Law Rep. 209.

A patent may be granted by Congress for an invention which was in public use and enjoyed by the community at the time of the passage of the act granting the patent. Blanchard 7'. Sprague, 2 Story (U. S.) 164; s. c., 3 Sumn. (U. S.) 535; s. C., I Robb Pat. Cas. 724; Evans v. Jordan, I Brock (U. S.) 248; s. c., 9 Cranch (U. S.) 199; s. c., 1 Robb Pat. Cas. 20; Jordan v. Dobson, 4 Fish. Pat. Čas. 232; Blanchard's Gun-Stock etc. Factory v. Warner, 1 Blatchf. (U. S.) 258; Yuengling v. Schile, 12 Fed. Rep. 97; Bloomer v. McQuervan, 14 How. (U. S.) 539; McClurg v. Kingsland, 1 How. (U. S.) 202; s. c., 2 Robb Pat. Cas. 105; United States v. Burns, 12 Wall. (Ü. S.) 252; Cammeyer v. Newton, 94 U. S. 234; McKeever v. United States, 23 Pat. Off. Gaz. 1527.

2. U. S. Rev. Stat., §§ 475-496.

3. U. S. Rev. Stat., § 476. The succeeding paragraphs of the statute define the duties of the Commissioner.

is

Residence. The official residence of the Commissioner of Patents Washington, D. C. Butterworth v. Hill, 114 U. S. 128.

4. U. S. Rev. Stat., § 480.

Inventions by Patent Office Em

ployees.-A person, however, who makes an invention before he comes into the government's employ, does not forfeit his right. He cannot take out a patent while he is an employee, but can so soon as his employment ceases, and no change in his status is caused by the fact of his employment. Page v. Holmes etc. Tel. Co., 17 Pat. Off. Gaz. 737; s. c., I Fed. Rep. 304; s. c., 5 Bann. & Ard. Pat. Cas. 165.

After the expiration of employment, a patent may be taken out even though the invention was made during the employment. And it may also be carried back to its actual date. Foote v. Frost, 3 Bann. & Ard. Pat. Cas. 607; s. c., 14 Pat. Off. Gaz. 860.

5. U. S. Rev. Stat., § 481. And has charge of all books, records, papers, models, machines and other things belonging to the Patent Office. Other statutory powers named in the immediately following sections are the classification of models, etc., and returning models in rejected cases.

4. Qualification and Duties of Examiners-in-Chief.-The Examinersin-Chief must be persons of competent legal knowledge and scientific ability. Their duties are, on the written petition of the appellant, to revise and determine upon the validity of the adverse decisions of examiners upon applications for patents, and in interference cases.1

5. Practice of Patent Office.-The Commissioner of Patents, subject to the approval of the Secretary of the Interior, may, from time to time, establish regulations not inconsistent with law for the conduct of proceedings in the office.2

6. Caveats (a) WHO MAY FILE.-Any citizen of the United States, or any alien who has resided in the United States one year next preceding the filing, and who has made oath of his intention to become a citizen, who makes any new invention or discovery, and desires further time to mature it, may file a caveat. This contains a description of the device with its distinguishing features and a prayer for protection of the caveator's right until he shall have matured his invention.4

(b) DUTIES OF PATENT OFFICE.-Upon receipt of a caveat, it is filed in the confidential archives of the Patent Office and preserved in secrecy, and is operative for one year from its filing.5

(c) PURPOSE OF CAVEAT.-A caveat protects the inventor from the granting of any patent for an interfering application without his knowledge, and gives the caveator, who has exercised due diligence in reducing his invention to practice, the right to carry back his invention to the date of the filing of the caveat."

1. U. S. Rev. Stat., § 482. When required by the Commissioner, they shall hear and report upon claims for extensions and perform such other duties as he may assign to them.

2. U. S. Rev. Stat., § 483. Authority of These Rules.-"Congress, in creating the Patent Office, has, by express legislation, given that office the power to enact rules for its conduct. Those rules, if within the powers of the office, are as authoritative as the laws of Congress itself within the limitation of its powers. United States v. Thacher, 7 Pat. Off. Gaz. 603. 3. U. S. Rev. Stat., § 4902. 4. U. S. Rev. Stat., § 4902.

5. U. S. Rev. Stat., § 4902. "And if application is made within one year by any other person for a patent with which such caveat would in any manner interfere, the Commissioner shall deposit the description, specification, drawings and model of such application in like manner in the confidential archives of the office, and give notice thereof, by mail, to the person by whom the caveat was filed. If such

person desires to avail himself of his caveat, he shall file his description, specifications, drawings and model within three months from the time of placing the notice in the post-office in Washington, with the usual time required for transmitting it to the caveator added thereto; which time shall be endorsed on the notice.

6. Bell v. Daniels, 1 Fish. Pat. Cas. 372; s. c., 1 Bond (U. S.) 212; Allen v. Hunter, 6 McLean (U. S.) 303, American etc. Pavement Co. v. Elizabeth, 6 Fish. Pat. Cas. 424; Hildreth v. Heath, Cranch Pat. Dec. 96; s. c., vol. 2, Pat. Off. Rep. of 1847, p. 804.

A patent for the same invention as that described in the caveat granted during the pendency of the caveat is not void. Cochrane v. Waterman, Cranch Pat. Dec. 121.

The proper practice where a caveat is accidentally overlooked, and a patent granted to another during its pendency, is to grant a patent to the caveator. Phelps v. Brown, I Fish. Pat. Cas. 479; s. C., 4 Blatchf. (U. S.) 362. 7. American etc. Pavement Co. v.

7. Petition. An inventor must make application in writing to Commissioner of Patents for a patent for his invention.1

8. Model. In all cases which admit of representation by a model, a model of convenient size to exhibit the parts of the device,2 and, when the invention is of a composition of matter, specimens of the ingredients and of the composition in sufficient quantity for experiment, shall be furnished by the applicant if required by the Commissioner.4

9. Oath-Contents.-The applicant must make an oath, that he does verily believe himself to be the original and first inventor of the invention for which he solicits a patent, that he does not believe the same was ever before known or used, and shall state of what country he is a citizen.5

Officer to Administer.-In the United States, any officer authorized by law to administer oaths. When the applicant resides in a foreign country any minister, chargé d'affaires, consul, or commer

Elizabeth, 6 Fish. Pat. Cas. 424; Phelps v. Brown, 1 Fish. Pat. Cas. 479; s. c., 4 Blatchf. (U. S.) 362; Allen v. Hunter, 6 McLean (U. S.) 303; Hoe v. Kahler, 12 Fed. Rep. 111.

It is not necessary for an applicant who desires to carry his invention back of the date of its perfection and reduction to practice, to have a caveat filed in order to be able to anticipate one who has in the meantime perfected his invention, or even obtained a patent. Hildreth v. Heath, Cranch Pat. Dec. 96; s. c., vol. 2, Pat. Off. Rep. of 1847, p. 804.

Caveat Not a Substitute for Diligence in Reduction to Practice.-A caveat will not protect an imperfect invention in perfecting which, due diligence has not been employed, against one who has subsequently made the same invention and reduced it to practice in a practical machine. Johnson v. Root, I Fish. Pat. Cas. 351. Nor against an intervening public use. Bell v. Daniels, 1 Fish. Pat. Cas. 372; s. c., I Bond (U. S.) 212.

Caveat Not an Admission that the Invention is Imperfect.-A caveat is not conclusive evidence that the invention is imperfect. A person may choose to file a caveat while he is going on and making improvements upon an invention which he has already completed so that it is of practical utility. Johnson v. Root, 1 Fish. Pat. Cas. 351.

Caveat by Sole Inventor Does Not Estop Him from Declaring Invention Joint. --A caveat in the name of a sole inventor does not estop him and others

who have in fact made the invention, from carrying back the date of the joint invention to the date of the caveator's filing. Hoe v. Kahler, 12 Fed. Rep. 1II.

1. U. S. Rev. Stat., § 4888; Hogg v. Emerson, 6 How. (U. S.) 437. 2. U. S. Rev. Stat., § 4891.

3. U. S. Rev. Stat., § 4890. But the fact that such was not in reality furnished when required, does not invalidate the patent. Tarr v. Folsom, 1 Holmes (U. S.) 313; s. c., 5 Pat. Off. Gaz. 92; s. c., 1 Bann. & Ard. Pat. Cas. 24; Badische etc. Fabrik v. Cochrane, 16 Blatchf. (U.S.) 155; s. c., 4 Bann. & Ard. Pat. Cas. 215.

4. U. S. Rev. Stat., §§ 4890, 4891.
5. U. S. Rev. Stat., § 4892.

The omission to take an oath does not affect the validity of the patent. Whittemore v. Cutter, 1 Gall. (U. S.) 429; s. c., 1 Robb Pat. Cas. 28; Crompton v. Belknap Mills, 3 Fish. Pat. Cas. 536; Dyer v. Rich, 1 Met. (Mass.) 180.

A recital in the patent that necessary oath was taken, is conclusive. Seymour v. Osborne, 11 Wall. (U. S.) 516; De Florez v. Reynolds, 14 Blatchf. (U. S.) 505; s.c., 3 Bann. & Ard. Pat. Cas. 292.

But a broadening of the application after the death of the patentee without a new oath by the administrator renders the patent void. Eagle Mfg. Co. v. West etc. Mfg. Co., 18 Blatchf. (U. S.) 218; s. c., 2 Fed. Rep. 774; s. c., 5 Bann. & Ard. Pat. Cas. 475; s. c., 17 Pat. Off. Gaz. 1504. The jurat need not be dated. French v. Rogers, 1 Fish. Pat. Cas. 133. A change of words in a claim not broadening the invention but making it

cial agent holding commission under the United States, or notary public of the country.1

By Whom Taken.-The oath is taken by the inventor if living,2 otherwise by his administrator or executor.3

10. Specification (a) GENERALLY.-The specification must contain a complete description, but the drawings and models, if there are any, are to be taken into consideration in determining whether the specification is sufficiently clear,5 though the scientific principles on which the device operates need not be known to the inventor or set forth in the specification.

(b) SPECIAL RULES RELATING TO COMPOSITION OF MATTER. -The names of the ingredients, and, where the invention cannot. be used to advantage without naming them, the proportions must be stated.

(c) SPECIAL RULES Relating to COMBINATION.—In a combination the devices of which it is composed must be named, their mode of operation given and the new result pointed out.8

(d) CLEARNESS.-An inventor must file in the Patent Office a written description of his invention and the manner and process

clearer, does not require a new oath. Brush Electric Co. v. Julien Electric Co., 41 Fed. Rep. 679.

1. U. S. Rev. Stat., § 4892. Seymour v. Osborne, 11 Wall. (U. S.) 516. 2. U. S. Rev. Stat., § 4892. 3. U. S. Rev. Stat., § 4896.

4. Brooks v. Jenkins, 3 McLean (U. S.) 432; Dixon v. Moyer, 4 Wash. (U. S.) 68: s. c., 1 Robb Pat. Cas. 324; Head v. Stephens, 19 Wend. (N. Y.) 411; Wheeler v. Clipper Mower etc. Co., 6 Fish. Pat. Cas. 1; s. c., 10 Blatchf. (U. S.) 181; s. c., 2 Pat. Off. Gaz. 442.

A specification is not sufficiently clear which requires experiment and the solution of a problem before the device can be constructed. Webster Loom Co. v. Higgins, 105 U. S. 580; S. C., 16 Pat. Off. Gaz. 675.

5. Singer v. Walmsley, 1 Fish. Pat. Cas. 558; Earl v. Sawyer, 4 Mason (U. S.) 1; s. c., I Robb Pat. Cas. 491; Hogg v. Emerson, 6 How. (U. S.) 437; Burrall v. Jewett, 2 Paige (N. Y.) 134; Washburne v. Gould, 3 Story (U. S.) 122; s. c., 2 Robb Pat. Cas. 206; Holt v. Kendall, 26 Fed. Rep. 622.

But where a portion of the invention is not described at all in the specification, the fact that it is shown in the drawings is not sufficient. Gunn v. Savage, 30 Fed. Rep. 366.

6. Čahill v. Beckford, 1 Holmes (U. S.) 48; Andrews v. Cross, 19 Blatchf. (U. S.) 294; s. c., 8 Fed. Rep. 269.

A patentee is not confined to techni

cal terms. Hovey v. Stephens, 3 Woodb. & M. (U. S.) 17; s. c., 2 Robb Pat. Cas. 567.

A patent which is available for one use named by the inventor, is not invalid because it is not applicable to another use. Phillips v. Risser, 26 Fed. Rep. 308.

Specification has reference both to the technical "specification" and "claim." Wilson v. Coon, 18 Blatchf. (U.S.) 532; s. c., 2 Fed. Rep. 611; s. c., 14 Pat. Off. Gaz. 482; Badische etc. Fabrik v. Higgin, 15 Blatchf. (U. S.) 290; s. c., 3 Bann. & Ard. Pat. Cas. 462; s. c., 14 Pat. Off. Gaz. 414.

7. Wood v. Underhill, 5 How. (U. S.) 1; s. c., 2 Robb Pat. Cas. 588; Jenkins v. Walker, 1 Holmes (U. S.) 120; s. C., 5 Fish. Pat. Cas. 347; s. c., 1 Pat. Off. Gaz. 359; Tyler v. Boston, 7 Wall. (U. S.) 327.

A general rule for proportions is sufficient. Wood v. Underhill, 5 How. (U. S.) 1; s. c., 2 Robb Pat. Cas. 588; Goodyear v. Wait, 3 Fish. Pat. Cas. 242; s. c., 5 Blatchf. (U. S.) 468; Francis v. Mellon, 5 Fish. Pat. Cas. 153; s. c., 1 Pat. Off. Gaz. 48.

Where the amount of an article in a compound can be varied without affecting the result except in degree, the direction to use "a small quantity" is sufficient. Brooker v. Dows, 3 Bann. & Ard. Pat. Cas. 518; s. c., 15 Pat. Off. Gaz. 570.

8. Seymour v. Osborne, 3 Fish. Pat.

of making, constructing, compounding and using it, in such full, clear, concise and exact terms as to enable any one skilled in the art or science to which it appertains or with which it is most nearly connected to make, construct, compound and use the same.1