Air Currents in Mines Explain Copper Country Cavings
Engineer J. Jackson of Houghton explains in a Chicago paper that timbering in Michigan copper mines and air movement trigger cave-ins. He describes Calumet & Hecla and Tamarack use of timber, pillar support, and how large stoped areas at depth can shift rock and generate powerful air blasts felt near the surface.
MENTIONED IN THIS ARTICLE
Western Society of Engineers
Chicago
J. Jackson
Houghton
Michigan
Quincy
Calumet & Hecla
Quincey
Tamarack
Steel Shares and Market Conditions Report
United States Steel reports a slight quarterly dip due to a builders strike in New York and other cities. Car shortages linger and delays affect construction, yet the company remains financially solid with 9 percent preferred stock yields. Iron ore markets show unsettled forge and foundry pig iron, while Bessemer iron stays barely steady.
MENTIONED IN THIS ARTICLE
United States Steel Corporation
New York
Great Corporation
Bessemer
Pittsburg
Southern Iron
Also Mentioned on This Page
Kelam, Slud & Ge
Meath & Milligan
Bessemer Lumber CO
Edwin Bayliss
THE
Heath & Tilligan Paints
Apleseencses
Axendt
Steel
Davis & Fehr
Bessemer, Mich
Bassemar Mich
Jos. Lettwoop
Geo. L. Loore
Gogebee
Geo. Il
Arrer, Supt
Montreal Mining Company
Levin HH. Treverrier
General Merchantise
Parner
Jack, the Tailor
Garis
J. R. Johnson