"New manufactures" are the objects of this exclusive privilege. A manufacture under the statute, is construed to mean a vendible substance, either in the form of an en gine or material; the one the result of mechanical, the other, of chemical skill. Although the statute is silent on the head, the manufacture ought to be useful ; for the inventor makes affidavit to this effect. The manufacture must farther be adequate to the professed effect, other wise a patent for it is void. A philosophical principle, not embodied in a mechanical or chemical result, cannot lie protected by patent. Neither can a mere process, or method, unless producing, as most processes and methods do, a vendible substance. It is, therefore, incorrect to give, as a title to a patent, a method of producing certain specified effects. Neverthless this error is so common, that the courts of law have admitted, by indulgence, the term method to signify the thing produced by the me thod. Still an accurate title would avoid this style. The noblest of all mechanical inventions, the steam-engine, affords an example of the inapplicability of a patent to a mere principle. The principle discovered was the ex pansive force of steam ; but the patent protects the ma chine called the steam-engine.
The invented manufacture must be within this realm." This entitles to a patent right, not only the ori ginal inventor, hut likewise the importer of a foreign in vention. We first inquire, what is a new invention ? As nobody can claim as their invention the familiar material substances—which, although many of even these, chemi cally speaking, are compound, we may here assume as elementary—the most original invention, either mechanical or chemical, must necessarily be a compound. The newly invented compound may be, first, a new arrangement of what we have called elementary substances ; or, secondly, a new arrangement of substances already mechanically or chemically arranged ; or thirdly, an improvement in the way of addition to a previous mechanical or chemical ar rangement; or lastly, a new method or process of manu facturing articles already in common use, whereby they are produced in greater abundance, perfection, or cheap ness. All four modes of invention may be legally pro tected by patent.
In the first there can be no difficulty. The original materials alluded to are free to every one. An important consideration here occurs. Many have erroneously thought, that they do not infringe a patent right, although they adopt the principle and even the arrangement, if they merely vary the material ; or even if, in mechanical inven tions, adopting the same materials, they vary the form of the whole, or any of the parts. If the specified material
or form be essential to the principle, a change of either is out of the question. It is only where the material and form are not essential to the principle that such change is possible, and it is then on plain principles of justice an in fringement. The patentee generally guards this point,by specifying a certain material and form, and adding, " or any others suitable." When the invention is a new arrangement of either one or more old combinations, either with each other, or with elementary substances, if these old combinations be free, (i. e, not the subject of an existing patent,) the patent is good for the new arrangement, as much as if the parts had been elementary substances. If, again, one or more of the old combinations are the subjects of existing pa tents, although the patent is good for the new arrange ment, the right of the previous patentee remains entire ; so that the new patentee cannot practically construct or manufacture his invention, without the license of the pre vious patentee. If, however, the new patentee have alter ed the principle of any of these patent steps, he makes that step his own as a new inventinn.
Nearly connected with this s the 'hind object of a pa tent, namely, an improvement on en olready known engine or substance. A total variation of the principle is not an improvement, but a new invention. An improvement is built upon the previous arrangement as a basis, which is not interfered with. The patent is good for the improve ment only. A patent was taken by the inventor of an im proved movement in a watch, and was voided by being taken for the whole watch. It is plain, that an improve ment on a patent article, although legally an object of a patent, is practically useless to the patentee, without the license of the previous patentee to make use of his inven tion as the subject improved.
A new process for refining sugar, bleaching linen, &c. (both refined sugar and bleached linen being well known,) afford examples of the fourth and last object of a patent right above mentioned.
The discovery of another use, or other uses, of a ma nufacture already known, is not legally the subject of a patent.
An invention, however old in a foreign country, will be secured by patent to the person who first brings it into this country. It is within the statute, in so far as it is " new within this realm ;" and the public interest is con cerned in encouraging such additions to our own manu facturing skill. But, by the present law, a revived manu facture, which, however forgotten, and therefore virtually new to the country, was in use before " within the realm," cannot obtain a patent.