been reduced to practice. If it were the mere speculation of a philosopher, or a mechanician, which had never been tried by the test of experience, and never put into actual operation by him, the law would not deprive a subsequent inventor, who had employed his labor and his talents in putting it into practice, of the reward due to his ingenuity and enterprise. But if the first inventor reduced his theory to practice, and put his machine or other invention into use, the law never could intend, that the greater or less use in which it might be, or the more or less widely the knowledge of its existence might circulate, should constitute the criterion by which to decide upon the validity of any subsequent patent for the same invention. I hold it, therefore, to be the true interpretation of this part of the statute, that any patent may be defeated by showing that the thing secured by the patent, had been discovered and put in actual use, prior to the discovery of the patentee, however limited the use or the knowledge of the prior discovery might have been. "'105

In an action for the violation of a patent right to a machine for making cotton and wool cards, the same judge said that "it would not be sufficient to protect the plantiff's patent, that this specific machine, with all its various combinations and effects, did not exist

105 Bedford v. Hunt, 1 Mason, 302.

before; for if the different effects were all produced by the same application of machinery, in separate parts, and he merely combined them together, or added a new effect, such combination would not sustain the present patent which was taken out for the whole machine, any more than the artist who added the second-hand or repeater to a watch, could have been entitled to a patent of the whole watch."'106

In another case the same judge says, "The first inventor of a machine is entitled to the benefit of his invention, if he reduce it to practice and obtain a patent therefor; and a subsequent inventor, although without any knowledge of the prior existence of the machine, or communication with the first inventor, cannot, by obtaining a patent therefor, oust the first inventor of his right, or maintain an action against him for the use of his own invention."'107

A case in the English reports supplies an exception to the doctrine as to the priority of invention which will entitle the inventor to a patent as above laid down, namely, where the first inventor, though he reduces the invention to use, yet keeps it secret, and shows an intention not to give the public the benefit of it. It was the case of an improvement in

106 Whittemore v. Cutter, 1 Gallison, 482.

107 Woodcock v. Parker, 1 Gallison, 438. See also Bedford v. Hunt, 1 Mason's R. 302; Evans v. Eaton, 3 Wheat. R. 454; S. C. 1 Pet. C. C. R. 322; Reutgen v. Kanowrs, 1 Wash. C. C. R. 168; Dawson y. Follen, 2 Wash. C. C. R. 311.

the object-glass of telescopes, invented by Mr. Hall, but suppressed by him until Mr. Dolland had subsequently made the same invention and procured a patent for it, the validity of which was disputed on the ground that he was not the first inventor. But the patent was held to be valid.108

Mr. Justice Buller puts this case upon the ground that Dolland was the first publisher of the invention, but it cannot be supported upon this ground merely, since it would put the priority, not upon the circumstance of the invention, but of the publication, which would be contradictory to the current of the decisions. It must stand upon the ground that, as the first inventor did not give the public that advantage of his discovery which it was the intention of the patent laws to secure, he should not stand in the way of a subsequent inventor who should be ready to give the public such advantage, at the end of the period of the monopoly provided for by the patent laws.

Mr. Justice Washington has laid down a doctrine at variance with that of Dolland's case. He considered that the inventor lying by for ever so long a period, and not taking out a patent, or continuing to use his invention, did not thereby forfeit his right of a patent, and that he might thus stand in the way of a patent being granted to any other inventor of

108 2 H. Bl. 487. See also Forsyth v. Reviere, Chitty Jr's. Prer. of the Crown, 182, n.

the same thing. His decision divides itself into two propositions; first, that the inventor, by thus lying by, did not forfeit his own right; and second, that he might thus intercept others, and these two propositions are not identical, or equivalent to each other, for he might thus lose his own right, and yet a patent for a subsequent discovery of the same thing be defeated by him. Whether he forfeits, his right will be subsequently considered. There are strong 'reasons for holding that he may thus forfeit his right, and if it be so held, then the doctrine of Dolland's case may be well founded.

There is one case, however, where, by our law, the priority must be determined by the date of the patent, namely, that of simultaneous inventions by different persons, neither of whom is apprized of the other's invention; for in these circumstances, the party who has first obtained a patent is presumed to have a right until the contrary is shown, and it would be impossible to prove a prior or better right in another person. But if both applied at the same time for a patent, and their claims were referred to arbitrators, according to the statute, no patent could be granted unless the point of priority were decided in favor of one of them; and perhaps a case could hardly occur which could not be decided, if the claim turned merely upon the question of priority. It seems, however, from an English case,

that where there is no other ground of discrimination the priority of application would decide the right.10

It will appear, when we come to the subject of the specification, that the patentee must be entitled to a patent for all that he alleges himself to have invented, or his patent will be void. It follows, from this doctrine, or rather is included in it, that if the patentee is the prior inventor of only a part of what is patented, the patent will be void. 110

In a suit for an infringement of a patent for an improved iron carriage wheel, by which the weight was made to bear upon the circumference, instead of bearing upon the centre or nave, it appeared that a carriage wheel of wood and iron had been invented and used eleven or twelve years before, by Mr. Strutt, in which also the weight had been made to bear upon the circumference, the inventor of which died soon after the invention, which had not been followed up, no new wheels of the same description having been made after the first three made by the inventor himself. Mr. Justice Patteson instructed the jury that if it appeared that Strutt's wheel was on the same principles, and in substance the same wheel as the plaintiff's, and it had been used openly and in public, so that every body might see it, and that the use of it had continued up to the time of the

109

Forsyth v. Reviere Chitty Jr's. Prer. of the Crown, 182 n.

110 The King v. Cutler, 1 Stark. N. P. 354; Brunton v. Hawkes, 4 B. & Ald. 540.