Edward Douglass White, Missouri Pacific Railway Company v…
“ But when the necessary result of the contention is thus defined, its want of merit is, we think, self-evident, unless it can be said as a matter of law that there is such an identity as to public convenience, comfort, and safety between travel on a passenger service train and travel on a mixed train,-that is, a train composed of freight cars with a passenger car attached,-as to cause any exertion of legislative authority for the public welfare, based on a distinction between the two, to be repugnant to the Constitution of the United States. ”
