There is no trade or occupation which calls forth the inventive faculty to a greater degree than the machinist's. Whether it be in the direction of making some new tool, needed in some special work, or in devising a particular movement, or mechanical expedient, the machinist must be prepared to meet the issues and decide on the best structural arrangement.

Opportunities also come daily to the workers in machine shops to a greater extent than other artisans, because inventors in every line bring inventions to them to be built and experimentally tested.

A knowledge of the rights and duties of inventors, and of the men who build the models, is very desirable; and for your convenience we append the following information:

The inventor of a device is he who has conceived an idea and has put it into some concrete form.

A mere idea is not an invention.

The article so conceived and constructed, must be both new and useful. There must be some utility. It may be simply a toy, or something to amuse.

If A has an idea, and he employs and pays B to work out the device, and put it into practical shape, A is the inventor, although B may have materially modified, or even wholly changed it. B is simply the agent or tool to bring it to perfection, and his pay for doing the work is his compensation.

An inventor has two years' time within which he may apply for a patent, after he has completed his device and begun the sale of it. If he sells the article for more than two years before applying for a patent, this will bar a grant.

Two or more inventors may apply for a patent, provided each has contributed something toward bringing it to its perfected state. Each cannot apply separately. The patent issued will be owned by them jointly.

Joint owners of a patent are not partners, unless they have signed partnership papers respecting the patent. Because they are partners in some other enterprise, disconnected from the patent, that does not constitute them partners in the patent. They are merely joint owners.

If they have no special agreement with respect to the patent each can grant licenses to manufacture, independently of the others, without being compelled to account to the others, and each has a right to sell his interest without asking permission of the others.

An inventor is one who has devised an invention. A patentee is one who owns a patent, or an interest in one, be he the inventor or not.

The United States government does not grant Caveats. The only protection offered is by way of patent.

A patent runs for a period of seventeen years, and may be renewed by act of Congress only, for a further term of seven years.

An interference is a proceeding in the Patent Office to determine who is the first inventor of a device. The following is a brief statement of the course followed:

When two or more applicants have applications pending, which, in the opinion of the Examiner, appear to be similar, the Office may declare an interference.

If an applicant has an application pending, and the Examiner rejects it on reference to a patent already issued, the applicant may demand an interference, and the Office will then grant a hearing to determine which of the two is entitled to the patent.

The first step, after the declaration of interference, is to request that each applicant file a preliminary statement, under oath, in which he must set forth the following:

First: The date of conception of the invention.

Second: Date of the first reduction to writing, or the preparation of drawings.

Third: Date of making of the first model or device.

Fourth: When a complete machine was first produced.

These statements are filed in the Patent Office, and opened on the same day, and times are then set for the respective parties to take testimony.

If one of the parties was the first to conceive and reduce to practice, as well as the first to file his application, he will be adjudged to be the first inventor, without necessitating the taking of testimony.

If, on the other hand, one was the first to conceive, and the other the first to file, then testimony will be required to determine the question of invention.

The granting of a patent is not conclusive that the patentee was, in reality, the first inventor. The law is that the patent must issue to the first inventor, and if it can be proven that another party was the first, a new patent will issue to the one who thus establishes his right. The Commissioner of Patents has no right to take away the patent first issued. Only the Courts are competent to do this.

A patent is granted for the right to make, to use and to vend.

An owner of a patent cannot sell the right only to make, or to sell, or to use. Such a document would be a simple license, only, for that particular purpose.

A patent may be sold giving a divided, or an undivided right.

A divided right is where a State, or any other particular territorial right is granted. An undivided right is a quarter, or a half, or some other portion in the patent itself.

If an inventor assigns his invention, and states in the granting clause that he conveys "all his right and title in and to the invention," or words to that effect, he conveys all his rights throughout the world.

If the conveyance says, "all rights and title in and throughout the United States," he thereby reserves all other countries.

If a patent is issued, and the number and date of the patent are given, the assignment conveys the patent for the United States only, unless foreign countries are specifically mentioned.

To convey an invention or patent, some definite number or filing date must be given in the document, with sufficient clearness and certainty to show the intent of the assignor.

An invention does not depend on quantity, but on quality. It is that which produces a new and a useful result.

In the United States patents are granted for the purpose of promoting the useful arts and sciences.

In England, and in many other foreign countries, patents are granted, not on account of any merit on the part of the inventor, but as a favor of the crown, or sovereign.

Originally patents were granted by the crown for the exclusive privilege in dealing in any commodity, and for this right a royal fee was exacted. From this fact the term royalty originated.

An international agreement is now in force among nearly all countries, which respects the filing of an application in any country, for a period of one year in the other countries.

In making an application for a patent, a petition is required, a specification showing its object, use, and particular construction, followed by a claim, or claims, and accompanied by a drawing, if the invention will permit of it, (which must be made in black, with India ink), and an oath.

The oath requires the following assertions: That the applicant is the first and original inventor of the device, and that he does not know and does not believe the same was ever known or used before his invention or more than two years before his application.

He must also further allege that the invention was not patented or described in any printed publication here or abroad, and not manufactured more than two years prior to the application, and that he has not made an application, nor authorized any one to do so more than two years prior to his application.

The first Government fee is $15, payable at the time of filing, and the second and final fee is $20, payable at the time the patent is ordered to issue.

The filing of an application for patent is a secret act, and the Patent Office will not give any information to others concerning it, prior to the issue of the patent