tinguished from the old one; or, in the sense of the patent law, can entitle the manufacturer to a patent."
So much for the negative method of investigation of the subject of novelty in patents. We have discussed many cases of apparent novelty and have seen in what novelty does not consist. In accordance with the old saw, "You tell me what you're not, and I'll tell you what you are," we are now prepared to turn to what I have called the positive method of investigation and learn what is patentable novelty.
To answer the question, What is novel, so as to be patentable? is easier than the one we discussed in the first part of this paper. In a few words, there is patentable novelty when there is a different principle of operation; when there is a different result in kind, or when there is a new combination. It is for one or another of these reasons that a patent is ever granted. There may be other grounds apparently, but a closer investigation will show them to be but another species of the above family, and consequently to be classified with them in their application.
The first two of the three principles enumerated can best be treated of together. To repeat, there will be novelty when either the manufacture produced, or the manner of producing an old one is new. In the former case there must be something substantially new, different from what was before known. In the latter case the principle of the machine must be different. And, as I have shown before, a mere change of the form or proportions will not suffice, if both are the same in principle, structure, mode of operation, and produce the same result. This is true even if there is some small variance in some small matter for the purpose of evasion, or a color for a patent. There must be some principles different from any previously known.
This opens up the ancillary and important question, What is meant by "the principles of a machine"?
In Whittemore vs. Cutter, 1 Gall., 478, Judge Story says: "By the principles of a machine is not meant the original elementary principles of motion which philosophy and science have discovered, but the modus operandi, the peculiar manner or device for producing any given effect. If the same effects are produced by two machines by the same mode of operation, the principles of each are the same. If the same effects are produced, but by combinations of machinery operating substantially in a different manner, the principles are different."
In deciding whether the principles of a machine are new, there is one block over which we may stumble and which we should take care to avoid. There is danger of confusing form with principle. The question of what constitutes form and what principle is frequently a very nice question to decide. Judge Washington, in Treadwell vs. Bladen, 4 Wash., 706, has pointed out a road out of the confusion. "The safest guide," says he, "to accuracy in making the distinction is, to ascertain what is the result to be obtained by the discovery; and
