Capital Machine Tool Co.
Auburn, NY (The Railroad, Telegraph, Electric and Steamship Builders' Buyers' Guide, 1897)
Earliest reference we discovered was September, 1893 in The Iron Trade Review, listed under Vises.
We are quite certain this is the patent referred to in the below advertisement: Patent #488,600 - Vise - Julius J. Cowell, Weedsport, NY (8 miles from Auburn) - 12/20/1892
Circa 1910 we find references to the J. J. Cowell Machine Works. Mr. Cowell had many other inventions for machinery.
1893 Iron Trade Review
Railway and Locomotive Engineering-1896