Mahlon Pitney, Philadelphia Company v. Smith…
“ Cas. 1914C, 153, that the repair of bridges in use as instrumentalities of interstate commerce is so closely related to such commerce as to be in practice and in legal contemplation a part of it, it of course is evident that the work of the bridge carpenters in the present case was so closely related to defendant's interstate commerce as to be in effect a part of it. ”
