connected with each other. That is but a more convenient mode of carrying out the principle of the patentee." This instruction was affirmed by all the judges of the Common Pleas, on a rule to show cause why a new trial should not be granted, Tindal, C. J., saying: "It would be difficult to define how far the suggestions of a workman employed in the construction of a machine are to be considered as distinct inventions by him, so as to avoid a patent incorporating them taken out by his employer. Each case must depend upon its own merits. But when we see that the principle. and object of the invention are complete without it, I think it is too much that a suggestion of a workman, employed in the course of the experiments, of something calculated more easily to carry into effect the conceptions of the inventor, should render the whole patent void."1 § 123. From the distinctions thus taken between the cases in which the employer is the real author of the principle or plan of the invention, and those in which the servant, workman, or agent is such real author, it follows that, where the relation between the two parties amounts to a contract, by which one agrees to employ his inventive faculties in the service of another, and the workman, in the course of the employment, makes a substantive invention, the question will arise whether the employer can become the patentee of that invention without a written assignment. In a case tried before Mr. Justice Washington (in 1821), under the statute of 1793, the defence was set up under a special notice authorized by the act, that the plaintiff surreptitiously obtained the patent for a discovery of one Wimbly, who worked as a journeyman in the plaintiff's shop. The learned judge gave the following instruction: "If the jury are satisfied that the discovery was in reality made by Wimbly, they must be also satisfied that the patent was obtained in fraud of any right which such discovery bestowed upon Wimbly. For if, upon the evidence, you should be of opinion that Wimbly gave up his right of discovery to the plaintiff, by expressly or impliedly permitting him to encounter the trouble and expense of obtaining a patent, it cannot be affirmed that the plaintiff obtained the patent surreptitiously, or in fraud of Wimbly's discov 1 Allen v. Rawson, 1 Man. Granger & Scott, 551. It was certainly worthy of consideration, whether this improvement amounted to a distinct patentable subject. 2 ery." The authority of this instruction is not to be pressed beyond the precise issue in respect to which it was given. It was contended by the defendant, that, inasmuch as no assignment from Wimbly to the plaintiff appeared to have been made, the plaintiff's obtaining the patent must be deemed to have been. surreptitious, in relation to Wimbly, and that the patent was therefore void, under the clause of the act which permitted the defendant to show that the patentee "had surreptitiously obtained a patent for the discovery of another person." But this allegation was obviously capable of being rebutted by evidence that Wimbly acquiesced in the plaintiff's application for the patent; and it was in reference to the evidence which tended to show such acquiescence, and to the special issue raised, that the learned judge gave the instruction above quoted. But where, under a plea of the general issue, evidence should be offered that the patentee was not, but that a workman was, the real inventor, could the action be maintained without showing a written assignment, or a written contract that would operate as an assignment, even if the real inventor had acquiesced in the plaintiff's application? This is a distinct question from that which arises under the clause of the statute against surreptitious applications in fraud of the rights of the true inventor. When it is considered that, by the sixth section of the act of 1836, the right to the patent is vested in the inventor, who must himself take the steps requisite to the grant of the patent, and that, by the sixth section of the act of 1837, it is made necessary to the grant of a patent to an assignee, that an assignment should be previously recorded, and that the inventor should make oath to the specification, it can scarcely be doubted that, where the real author of the invention is any other person than the patentee, it is necessary that some contract capable of operating as an assignment should precede the issuing of the patent. But such a case is distinguishable from that of a workman who is employed and paid by one who has conceived the principle or plan of an invention, and who relies on the ingenuity of another to enable him to perfect the details and realize his conception. 2 Dixon v. Moyer, 4 Wash. 68, 71. CHAPTER IV. OF THE EXTENT TO WHICH THE PRINCIPLE OF AN INVENTION MAY BE CARRIED BY LETTERS-PATENT. - WHAT IS MEANT BY PATENT § 124. NOTWITHSTANDING the ambiguity which of necessity attends the use of the term "principle," there is probably no other more convenient term with which to introduce the discussion to which the present chapter is to be devoted. I design to consider, as a branch of the general topic of what may be the subject-matter of a patent, that very difficult question, of how far a discovery or invention which may first disclose and practically embody some truth in physics or some law in the operation of the forces of nature, for a useful purpose, is capable of being carried in the exclusive privileges secured by the grant of letters-patent. The discussion of this question, when followed into some of the adjudicated cases, will be found to be connected with the construction of particular specifications. So, too, it enters into the whole subject of infringements, when the question is whether what the defendant has done. is within the scope of the patent that may be before the court in a given case. But notwithstanding the necessity of anticipating, to some extent, what it may be necessary hereafter to say on the topics of construction and infringement, it may be useful to consider the special question, which can, perhaps, be best stated as follows: How far can the characteristic principle of a discovery or an invention be made to extend by letters-patent, when that principle consists in a novel and useful application of some physical law, property of matter, or natural force ?1 Perhaps the best method for the treatment of this subject will be to select some prominent and peculiar invention, as an illustration of the question, and group the general principles and the prior and subsequent cases around it. By this method it will be Although the reader may object to the terms in which this question is propounded, it is believed that he will have no difficulty in discovering what it is that the writer means to discuss. Considerable difficulty must always attend the use of any terms by which we attempt to designate so abstract and abstruse a subject. seen to what extent the doctrines of the law may be regarded as settled. A very apposite illustration for this purpose is afforded by the invention of the magnetic telegraph. § 125. Morse, availing himself of the fact that a current of electro-magnetic fluid may be transmitted from place to place, along a wire, and at the terminus opposite to that from which the fluid proceeds may be used as the means of moving a delicate instrument, adapted an apparatus for throwing a current of such fluid along the wire, and for recording certain signs or marks, according to a system invented by him, at the farther extremity of the wire, by means of the movements of a recording instrument there suspended, and operated upon by the electro-magnetic current. Adopting the results of an adjudication, I assume that he was the first person who, by means of newly invented machinery adapted to the purpose, embodied and made of practical utility the fact in nature that the electro-magnetic current may be used at long distances as a moving force, for the purpose of recording or marking at pleasure intelligible signs or marks. On this hypothesis, the scope of his invention was the application and use of the electro-magnetic fluid, by means of suitable machinery and a concerted system of signs or marks, to the recording of intelligible signs or marks at a long distance from the operator. How far could he make this characteristic or principle of his invention the subject of an exclusive privilege under letters-patent? Could he patent the application and use of the electro-magnetic current, for this purpose, by any and all machinery which would effect the end proposed? or could he patent only the machinery by which he himself effected this application and use, and all other means which were substantially the same? § 126. This very grave question arose upon a claim in the early patent obtained by Morse, which was in these words: "I do not propose to limit myself to the specific machinery, or parts of machinery, described in the foregoing specifications and claims; the essence of my invention being the use of the motive-power of the electric or galvanic current, which I call electro-magnetism, however developed, for marking or printing intelligible characters or signs at any distances, being a new application of that power, of which I claim to be the first inventor or discoverer." It was not denied by the Supreme Court of the United States that he was the first inventor or discoverer of this application and use of the electro-magnetic current; but a great difference of opinion arose among the judges on the validity of this claim; a majority of the court holding it to be invalid, as being a claim without any limitation in respect to the means by which the electro-magnetic current could be used for the purpose described.1 It is not intended here to state the different views of the judges, or to comment upon. the decision. The case is now referred to only as an illustration of the subject before us. § 127. It has often been laid down that a mere elementary principle cannot be made the subject of a patent. What has been meant by this, it is of course important to ascertain. One of the earliest cases in which this topic came into consideration was that which arose upon Watt's invention of a separate condenser for the steam-engine. In the engines which preceded Watt's, the steam was condensed in the body of the cylinder. He discovered that, by condensing the steam in a separate vessel, and keeping the cylinder from cooling down, a great saving of steam, and by consequence of the fuel used to produce it, would be effected. In the unskilful fashion of that age, his patent was taken for "a newly invented method of lessening the consumption of steam and fuel in fire-engines"; and his enrolled specification proceeded to state that this method consisted of certain principles, the chief of which consisted in certain modes of preventing the cylinder from being cooled down below the temperature of the steam which entered it, and in the introduction of a separate condensing vessel or vessels. He did not describe any particular engine built according to his method, but a special verdict found that the specification was sufficient to enable a mechanic acquainted with the old engines to build an engine that would operate upon his plan and produce the new proposed effect of saving steam and fuel. It so happened, that, at the time when the action was brought in which this special verdict was found, Watt was entitled to sue by virtue of a special act of Parliament which had extended his patent for twenty-five years, but which had described it as a patent for making and vending certain engines, and which vested in him the sole right to make and vend the engines described therein. The special ver 1 O'Reilly v. Morse, 15 Howard, 62. |