“ It is almost impossible, in some matters, to foresee and provide for every imaginable and exceptional case, and a legislature ought not to be required to do so at the risk of having its legislation declared void, although appropriate and proper upon the general subject upon which such legislation is to act, so long as there is no substantial and fair ground to say that the statute makes an unreasonable and unfounded general classification, and thereby denies to any person the equal protection of the laws. ”

“ He may be none the less a dealer, selling in the usual course of his business, because he is also a manufacturer of the article dealt in. Exceptional and rare cases, not arising out of the sale of patented things in the ordinary way, may be imagined where this general classification separating the merchants and dealers from the rest of the people might be regarded as not sufficiently comprehensive, because in such unforeseen, unusual, and exceptional cases the people affected by the statute ought, in strictness, to have been included in the exception. ”

“ In a classification for governmental purposes there cannot be an exact exclusion or inclusion of persons and things. See Gulf, C. & S. F. R. Co. v. Ellis, 165 U.S. 150, 41 L. ed. 666, 17 Sup. Ct. Rep. ”