Shaft sinking
Subject
Subject Source: Library of Congress Subject Headings
Found in 1 Collection or Record:
Shaft Sinking Apparatus Patents
Collection — Sc_box MS 2, Folder: 20
Identifier: MS-612
Abstract
Patents, 1943-1944, issued to John Murray Riddell for improvements to mine shaft sinking apparatus. Includes patent issued by the United States in 1943 as well as a patent issued by the Union of South Africa, a dominion of Great Britain.
Dates:
1943-1944