Samuel Blatchford, Fay v. Cordesman — Opinion of the Court
“ Previously to my discovery of running the upper end of the web or scroll saw in frictional contact with an upper guide it was deemed an impracticable thing, and it is now only by practical demonstration and long use that saw-mill men are convinced rapidly wear out the guide. ”
Samuel Blatchford, Fay v. Cordesman — Opinion of the Court
“ As is well known, the high speed at which these saws are driven, and the small amount of surface presented to the guide from the edge of the saw-plate, cause fixed guides to wear away very fast, even if made of hardened steel or glass, particularly when heavy sawing is done, and the strain of the feed falls on the saw. Rolling guides, while they have partially overcome the difficulty of friction and wear on the back of the saw, cannot be constructed to give a proper lateral support to the saw, as will hereafter be alluded to. ”
Samuel Blatchford, Fay v. Cordesman — Opinion of the Court
“ The defendants have used a wheel which has two grooves in it, in one of which the saw runs and in either of which it can run. The wheel can be adjusted laterally, so as to bring the one or the other of the two grooves into use. But there is no adjustment to bring different points of the periphery of a smooth-faced wheel into use. In view of the state of the art and of the limitations of the specification there has been no infringement. Merely adjusting a wheel laterally, so as to give it different positions at different times, was a thing well known to mechanics ”
