That which may be put into beneficial practice. 2. The patent act of congress of July 4, 1836, sect. 6, in describing the subjects of patents, mentions new and useful art, and new and useful improvement. To entitle the inventor to a patent, his invention must, to a certain extent, be beneficial to the community, and not be for an unlawful object, or frivolous, or insignificant. By “useful” in the patent law, is meant not an invention in all cases superior to the modes now in use for the same purposes, but “useful,” in contradistinction to frivolous and mischievous, invention. By “useful” is meant such an invention as may be applied to some beneficial use in society, in contradistinction to an invention which is Injurious to the morals, the health, or the good order of society.
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