Of an invention acknowledged new quoad the public, it is often disputed who is the first inventor. If neither claimant in a competition have published his discovery, the priority must be determined by legal evidence. This is the case which generally occurs, when a patent is yet unobtained by either party. But an infringer of a patent, or any one having interest, may show that the thing, though likewise the invention of the patentee, was invented be fore. The only legal evidence of priority however is, that it was publicly used before. An invention kept secret, will not annul a subsequent bona fide invention of the same thing, as in the case of the achromatic telescope. Even a dis closure of the previous invention to one person is not suf ficient; but it has been held previous publication, that it was disclosed to two. This point is not well settled; for it has been held that actual public use is necessary; and certainly when the question is, as it ought to be, who is the beneficial inventor, it cannot be doubted that it is the first public user, he always being bona fide inventor like wise. Sale, in the way of trade, of the patent article is undoubted public use. On the other hand, publication of the secret in any way, even accidentally or by a malicious opponent, before the patent is rendered safe by passing the great seal, voids the right. This is on the principle, that the disclosure, de facto, incapacitates the inventor from fulfilling his engagement to the public, by disclosing the invention ; for no man can disclose what is already dis closed. The utmost caution is therefore necessary, in the inventor, to preserve the secret till the patent is sealed; insomuch, that the Lord Chancellor Eldon once declared from the bench, that if he were maturing an invention, and soliciting a patent, he would not entrust with the se cret his own brother ! We cannot help remarking, that the effect given to such disclosure, does not seem to quad rate with the principle of previous public use alone vacat ing the patent.
Of course, the patentee must be the sole inventor. Even a hint from another person has been found fatal to a patent.
Whenever an inventor has made up his mind to apply for a patent, he ought to lodge a caveat, as it is called, at the offices of the attorney and solicitor general, desiring notice of all patents applied for, for the same or the same sort of invention. This request is generally stated broad ly, to be the more certain of including the particular in vention. 'I he precaution is important to an ingenious person, who is engaged in a series of difficult and expen sive experiments, but who has not sufficiently matured his invention to enable him to apply for a patent. It is not less useful to the inventor, whose patent, although applied for, has not passed the great seal ; and it is not unimpor tant to a person actually in possession of a patent, that he may oppose all subsequent applications for patents for the same invention. This is the sum of the virtue of a
caveat ; which has been so much mistaken as to be held to be a sort of minor patent, which, by its own opera tion, stays the hands of all persons engaged in similar in ventions.
When notice is given by the attorney or solicitor gene ral of a rival application, the lodger of the caveat must appear personally, or by proxy, before one or both of these law officers, and lay before them his invention, with evi dence, if necessary, of its date, progress, Sze. The rival applicant does the same. Each case is considered sepa rately and privately; and the law officers decide upon the question of priority, if the inventions are the same, or of difference, if different; in which last case each will be en titled to a patent. When neither point can be determined, they generally recommend a joint patent.
The inventor, even previous to his caveat, having often recourse to the aid of workmen and others, and of the capital of friends for his experiments, it is lawful to bind such persons to secrecy, under contract of paying him a sum of money for taking any undue advantage. This sum must not he called a penalty, but be expressly stipulated to be liquidated damages. So it has been decided.
When the invention is completed, the inventor applies to the king by petition, accompanied by affidavit, sworn before a master in chancery, or a magistrate in the country, setting forth that he is the first and sole inventor; that the invention will be of public benefit ; and that it has never been in previous use to the best of his belief. This the first document contains the title of the invention, which ought to be well considered, as it cannot afterwards be al tered. The petition is referred by the king to his attorney and solicitor general It is here that the opposition on caveat, if any, takes place, as already mentioned. If there be no opposition, or it have been met and defeated, the Iaw officers report to the king that the invention is worthy of a patent. It is very important to observe, that this fa vourable report is a matter of course when there is no op position ; and this marked qualification is contained in the report : " As it is entirely at the hazard of the said peti tioner whether the said invention is new, or will have the desired success." A bill is then prepared as a warrant, and signed with the sign manual. This, after several offi cial steps, well known in practice, and detailed in all the law books on the subject, authorizes the letters-patent to be made out at the lord chancellor's office, wityrtE THE