Tooele Transcript Bulletin | 1907-07-05 | Page 5 | For Hardening Drill

1 for or hardening drill an oid inai drill in sulphuric ua hold add states the I 1 anglish mechanic makes an dge that will nill cut tempered stell or tate cutting haril hard rock hie acid should be poured into a hat flat bottomed essl to a depth ol of about one eighth of an inch the point of ohp dill I 1 Is hi h atod lo 10 a dull eh ch try i ry I 1 i d and dipped in ili the acid to that depth I 1 his mak s the point ext imoh hard hll h hi jemai rider rem tins ilna soft if tin ill point breaks r but bul alili ich a little poo acid la in tho the v vi a pi el