in the grant of letters patent, where there is a meritorious invention. Yet it would be a grave error to found upon such decisions a rule of action for the Commissioner; for it by no means follows, because a patent has been sustained, notwithstanding certain informalities in the issue, that every succeeding patent is to exhibit the same informalities. In Tompkins v. Gage (2 Fish., 580) it was held, that the second claim of the patent under consideration was but a repetition of the first; but that "duplicity of claim" did not affect the validity of the patent. It could hardly be gravely contended, however, that upon the authority of this decision the Commissioner should encourage or permit the granting of duplicate claims.

The whole question is one of discretion in the Commissioner.

It may be conceded that it is difficult to establish any general rule for the division of inventions into separate patents, which shall apply to all cases, or which shall not be subject to many exceptions. In both of the cases quoted, it is suggested that the union of many inventions in one patent would deprive the Government of its proper fees. This is a legitimate consideration. A fee of $15 is now charged for examination into the novelty, utility, and patentability of an invention. This is a very reasonable charge, and is much less than it would cost to make the examination in any other way. Indeed, the fees for all services in the Patent Office are less than are charged in any other country, while the service performed for the applicant by the office is much greater.

It would be unjust to the Government, to the public at large, and to other inventors, to permit one of their number to present a batch of inventions for examination

under a single fee, for he would receive more of the time of the examiner than he had paid for. Another consideration, which is not less important, is found in the classification of the various subjects of invention, and the assignment of the different classes to different examiners. This division of labor is absolutely essential to the prompt and thorough examination of applications. It is adopted to facilitate the transaction of the public business, and the inventor himself is directly and immediately benefitted by a strict adherence to it. Any union of inventions in one patent, that would seriously impair this classification, ought not to be permitted. Besides the delay and increased difficulty in making the examination, if the patent covers devices which enter into two classes, the drawing, which is single, must be deposited in the portfolio of the one class, and be wanting in the portfolio of the other. It may thus be overlooked in the examination of the next case.

It may therefore be said in general, that when two or more distinct inventions are united in one application that are capable of division, and which belong to different classes, or involve a double labor of examination, or have no community of operation, it is not only the right, but it becomes the duty of the Commissioner to require the application to be divided. (Linus Yale, jr., ex parte, Commissioner's Decisions, 1869, p. 110.)

51. Pending applications preserved 56. Delays at the Patent Office.

46. APPLICATION TO BE MADE TO THE COMMISSIONER OF PATENTS.-Before any inventor or discoverer shall receive a patent for his invention or discovery, he shall make application therefor, in writing, to the Commissioner, &c. (Act of July 8, 1870, § 26.)

47. TIME TO COMPLETE AND PROSECUTE APPLICATIONS.All applications for patents shall be completed and prepared for examination within two years after the filing of the petition, and in default thereof, or upon failure of the applicant to prosecute the same within two years after any action therein, of which notice shall have been given to the applicant, they shall be regarded as abandoned by the parties thereto, unless it be shown to the satisfaction of the Commissioner that such delay was unavoidable. (Act of July 8, 1870, § 32.)

48. CLERICAL REQUIREMENTS.-The application must be in writing, in the English language, and addressed to the Commissioner of Patents. The petition and specification must be separately signed by the inventor. All claims and specifications filed in this office (including amendments) must be written in a fair, legible hand, without interlineations or erasures, except such as are clearly stated in a marginal or foot note, written on the same sheet of paper; otherwise the office may require

them to be printed. All the papers constituting the application must be attached together. (Patent Office Rules, July, 1870.)

49. APPLICATION SHOULD BE COMPLETE WHEN FILED.No application can be examined, nor can the case be placed upon the files for examination, until the fee is paid, the specification, with the petition and oath, filed, and the drawings and model or specimen (when required) filed or deposited. It is desirable that everything necessary to make the application complete should be deposited in the office at the same time. If otherwise, a letter should accompany each part stating to what application it belongs. (Ib.)

50. RULES OF CORRESPONDENCE.-All correspondence must be in the name of the "Commissioner of Patents," and all letters and other communications intended for the office must be addressed to him. If addressed to the Acting or Assistant Commissioner, chief clerk, examiners, or any of the other officers, they will not be noticed, unless it should be seen that the mistake was owing to inadvertence. A separate letter should in every case be written in relation to each distinct subject of inquiry or application, the subject of the invention and the date of filing being always carefully noted. (Ib.)

When an agent has filed his power of attorney, duly executed, the correspondence will, in ordinary cases, be held with him only. A double correspondence with him. and his principal, if generally allowed, would largely increase the labor of the office. For the same reason the assignee of an entire interest in an invention is entitled to hold correspondence with the office to the exclusion of the inventor. If the principal becomes dissat

isfied, he must revoke his power of attorney and notify the office, which will then communicate with him. (1b.) Whenever it shall be found that two or more parties whose interests are in conflict are represented by the same attorney, the examiner in charge will notify each of said principal parties of this fact, and also the attorney. (Ib.)

All communications to and from the Commissioner upon official business are carried in the mail free of postage. (Ib.)

All business with the office should be transacted in writing. Unless by the consent of all parties, the action of the office will be predicated exclusively on the written record. No attention will be paid to any alleged verbal promise or understanding in relation to which there is any disagreement or doubt. (Ib.)

51. PENDING APPLICATIONS PRESERVED IN SECRECY.After a second rejection, none of the papers can be inspected, save in the presence of a sworn officer, nor will any of the papers be returned to the applicant or agent. (Ib.)

Aside from the caveats which are required by law to be kept secret, all pending applications are, as far as practicable, preserved in like secrecy. No information will therefore be given those inquiring whether any particular case is before the office, or whether any particular person has applied for a patent. (Ib.)

Information in relation to pending cases is given so far as it becomes necessary in conducting the business of the office, but no further. Thus, when an interference is declared between two pending applications, each of the contestants is entitled to a knowledge of so much of his