Hill, John A. (John Alexander), 1858-1916, Sinclair, Angus, 1841-1919 · New York : American Machinist Pub. Co · leaf 73
331.JOI, Hospitalfund 15 railroad English lor a hold up BV WM, FOSTER. 1 send you a print of a boiler squarewhich I made, and which has proved agood tool. There is great difficulty withthe average mechanic in drilling holes ina boiler to get them central, and in put-ting valves in on theboiler… … squares, all imperfect, for the reason of thedifference in the size of boilers, necessitat-ing a different square for each size. Toovercome all difficulties I made this square,which will enable anyone to drill hidesand tap them central with the boiler. Thesketch explains itself, the projecting…
Railroads · Locomotives
Internet Archive · Carnegie Library of Pittsburgh · Public Domain Mark 1.0. Free to use for anything.
