upon the result of an examination in the Patent Office, as will also the third to some extent.

3. To enable the Commissioner to come to a correct conclusion in regard to the third point of inquiry, the applicant should, if possible, procure the testimony of persons disinterested in the invention, which testimony should be taken under oath [in the form of interrogatories, as in form, marked XXVIII., page 103.

4. In regard to the fourth and fifth points of inquiry, in addition to his own oath, showing his receipts and expenditures on account of the invention, by which its value is to be ascertained, the applicant should show, by the testimony of disinterested witnesses on oath that he has taken all reasonable measures to introduce his invention into general use, and that, without default or neglect on his part, he has failed to obtain from the use and sale of the invention a reasonable remuneration for the time, ingenuity, and expense bestowed on the same, and the introduction thereof into use.

5. The report of the Examiner upon the novelty and utility of the invention will be ready fifteen days before the day appointed for the hearing, which report will be open for inspection at the Patent Office, copies of which will be furnished to all parties interested, if desired, on payment of the usual fees for copies.

6. In cases of opposition by any person to the extension of a patent, both parties may take testi

mony, &c., [as previously related in cases of "Interference."]

7. Generally, the monopoly of an invention is secured by law to the inventor for a period of fourteen years. This is done with a view to compensate him for his time and expense in originating and perfecting it. At the end of the time for which his patent runs, the monopoly ceases, and the invention becomes public property, unless the patentee can show good reasons to the contrary. The presumption is always against his application; and if he cannot show that his invention is novel, useful, valuable, and important to the public, and that, having made all reasonable effort to introduce. it into general use, he has not been adequately remunerated for his time and expense in discovering and perfecting it, the Commissioner cannot grant an extension. Rarely, indeed, are patents extended in this country. Some instances have occurred, when, against the decisions of the Commissioner, or owing to informalities, resort has been had to Congress for extensions; but, besides the impolicy to the public, of seeking this channel for redress, itself of doubtful expediency, it is a question how far Congress can control the final action of the Commissioner in such cases.

XXVIII. Form of Deposition.

1. A. B., being duly sworn, doth depose and say, in answer to interrogatories proposed to him by C. D., counsel for E. F., as follows, to wit:

(1.) "Interrogatory. What is your name? Your age? residence? occupation?

(1.) "Answer. My name is A. B.; my age thirty years; I am a carpenter; reside in Boston, Massachusetts."

[Then follow other interrogatories and answers.] And in answer to cross-interrogatories proposed to him by G. H., counsel for I. K., doth depose and say as follows, to wit: (1.) "Interrogatory. (1.) "Answer." [&c., &c.

(Signed by the deponent)

2. State of New York,

Rensselaer county, S

SS:

"A. B."

At Troy, in the said county, on the first day of January, 1855, before me personally appeared the above named A. B., and made oath that the foregoing deposition, by him subscribed, contains the whole truth, and nothing but the truth. The said deposition is taken at the request of E. F., to be used upon the hearing of an interference between the claims of the said E. F., and those of I. K., before the Commissioner of Patents of the United States, at his office, on the day

of

next. The said I. K. was duly notified, as appears by the original notice hereto annexed, and attended by G. H., his counsel.

"L. M.,

"Justice of the Peace."

3. After which, the magistrate shall seal up the deposition and accompanying papers, according to

the manner described and directed in XXVI., page 99.

XXIX. Assignment of a Patent.

1. Any inventor may, "by any instrument in writing," assign the whole or a part of his interest in such invention or discovery before or after he obtains a patent therefor. The language of the law is, "That every patent shall be assignable in law, either as to the whole interest, or any undivided part thereof, by any instrument in writing; which assignment, and also every grant and conveyance of the exclusive right under any patent, to make and use, and to grant to others to make and use, the thing patented within and throughout any specified part or portion of the United States, shall be recorded in the Patent Office within three months from the execution thereof, for which the assignee or grantee shall pay to the Commissioner" "a fee of one dollar for recording any assignment, grant, or conveyance, of the whole or any part of the interest in letters patent, or power of attorney, or license to make or use the thing patented, when such instrument shall not exceed three hundred words; the sum of two dollars when it shall exceed three hundred, and shall not exceed one thousand words; and the sum of three dollars when it shall exceed one thousand words; which fees shall in all cases be paid in advance." [Sect. 11, act 1836, and sect. 2, act 1848.

2. "The assignee of the entire interest in an in

vention which has not been patented, may have the patent issued to himself on recording the assignment.

3. "The receipt of assignments for recording is not usually acknowledged, it being intended to have them recorded and returned in season to answer the same purpose." [Rules of Patent Office.

[Note. The act of 1836 authorized a charge for recording assignments, but the clause was subsequently repealed. The special act of 1848 restored the clause, as modified above; but as the provisions of that law are not generally understood, an erroneous impression prevails, that the recording is done gratuitously. For forms of assignments, see post XXX., page 106, and XXXI., page 107.]

XXX. Form of Assigning a Patent

"Whereas I, John Fitch, of Philadelphia, in the county of Philadelphia, and state of Pennsylvania, did obtain letters patent of the United States for certain improvements in steam engines, which letters patent bear date the first day of March, 1835; and whereas, John Doe, of Philadelphia, as aforesaid, is desirous of acquiring an interest therein, Now this indenture witnesseth, That for and in consideration of the sum of two thousand dollars, to me in hand paid, the receipt of which is hereby acknowledged, I have assigned, sold, and set over, and do hereby assign, sell, and set over, all the right, title, and interest which I have in the said