Section 4892. The applicant shall make oath that he does verily believe himself to be the original and first inventor or discoverer of the art, machine, manufacture, composition, or improvement for which he solicits a patent; that he does not know and does not believe that the same was ever before known or used; and shall state of what country he is a citizen. Such oath may be made before any person within the United States authorized by law to administer oaths, or when the applicant resides in a foreign country, before any minister, charge d'affaires, consul, or commercial agent, holding commission under the Government of the United States, or before any notary public of the foreign country in which the applicant may be.

27 Tucker vs. Tucker Mfg. Co., 4 Cliff. (U. S.), 397, 24 Fed. Cas. No. 14,227.

28 Brooks vs. Fiske, 15 How., 212.

But where a patent is granted without an oath, its omission does not affect the validity of the patent.29