An edition of Testimony in behalf of the extension of the patent of Cyrus Chambers, Jr., for improvements in paper-folding machines, no. 23,445, granted April 5, 1859 (1873)

Testimony in behalf of the extension of the patent of Cyrus Chambers, Jr., for improvements in paper-folding machines, no. 23,445, granted April 5, 1859

hearing March 19, 1873, before the commissioner of Patents

By Cyrus Chambers