Enter a name, company, place or keywords to search across this item. Then click "Search" (or hit Enter).
Collection: Directories and Documents > Pamphlets
Mining Methods in Grass Valley District California From Transactions of the American Institute of Mining and Metallurgical Engineers by J A Fulton and A B Foote (PH 2-6) (1927) (14 pages)
Go to the Archive Home
Go to Thumbnail View of this Item
Go to Single Page View of this Item
Download the Page Image
Copy the Page Text to the Clipboard
Don't highlight the search terms on the Image
Show the Page Image
Show the Image Page Text
Reset View and Center Image
Zoom Out
Zoom In
Rotate Left
Rotate Right
Toggle Full Page View
Flip Image Horizontally
More Information About this Image
Get a Citation for Page or Image - Copy to the Clipboard
Go to the Previous Page (or Left Arrow key)
Go to the Next Page (or Right Arrow key)
Page: of 14
Jong and not more than 8 in! high. ‘Much of the vei :
69 it is important to leave as much. of ects peceege is waste
s 41 ] [ 1 z a = stope as es
With a larger and heavier scraper, the miners would not dente ean
«o carefully as'when the ore was handled with shovels, as some atthe
yee vou. He puree under, the. large pile. The scraper now used fr
. of the LeClaire type, that is, a piece of angle iron bent at right angles so that the two legs make an’ angle of 45° with the surface on which it cata
i ' St
i i B. Foore (author's reply to discussion).—~The Empire and the
North Star are about equal in importance and are by far the two largest
. ,’ mines In the district;:;, Each employs: about the samo number of men;.
> at times tha production of ithe North Starhas beon larger, but at meen
+ that-of the Wnipire is larger.’ Both handle:about the same’ tonnage.
i" Tho State mining laws forbid the use of gasoline locomotives underground, besides there is danger of gasoline fumes accumulating in pockets
Bit where there is'no.ventilation. . A‘storage-battery locomotive is used on
“along haul where dilarge:tonnage.is handled!+:-Due to the smallness of
Ne the vein; the tonnage per, unit area is comparatively small, and mule
/shaulage-is cheaper than any other-kind when the whole output from one
> level.can be taken care of. by one driyer.per shift.
Small serapurs! ire, ised: not only. because of the importance ‘of sorfing
. out-iwhste, but, because only. 1: amall: tonnage is produced per unit area.
“os./A large seraper / would; clean ‘out the; whole, area within its reach in
im necessitating frequent moves'and it costs too much to move
r epee fo handle: a large scraper from one place