252 ANNUAL OF SCIENTIFIC DISCOVERY. 



100 to 1,000 feet, and that they are thicker and much more extensive 

 in the Western than in the Atlantic States. Yet in Alabama the 

 Artesian wells (not less than 500 in number) rarely exceed 600 feet. 

 True, the strata vary considerably in thickness in different prominent 

 localities. Thus, on two adjacent plantations, one man's well may be 

 only 400, while his neighbour's is 500 feet deep. Still the average 

 thickness is, as has just been stated, pretty accurately known, and 

 does not exceed 600 feet. This induces the belief that, as the auger 

 is known to have penetrated the strata several feet, perhaps fifty or 

 more, the city well can, in no event, exceed 1,500 feet, and that water 

 will probably be obtained at a much less depth. 



It will be necessary, however, to tube the well from top to bottom ; 

 otherwise the water, passing through such an extent of limestones 

 and marls, impregnated with soluble saline substances, will be very 

 impure. 



DRAINING THE MINES OF SIERRA-MORENA. 



AN English company have leased the celebrated silver mines of 

 Guadalcanal, in Seville, in Spain, which have been under water for 

 a period of 150 years. Before that time they produced to the Span- 

 ish government 100,000 per annum, in duties alone; and from the 

 proceeds of these the palace of the Escurial was built. They were 

 the property of the Fuchars, rich contractors ; \vho not satisfied with 

 the enormous wealth they derived from them, secretly took away the 

 ores from a new lobe they discovered, without giving notice to the 

 government, and, to prevent imprisonment and confiscation, they let 

 the water into the mines, and for 150 years they have remained in 

 the state in which they were thus left by them. About six months 

 ago, however, the mines were purchased by an English company on 

 the most advantageous terms, and the draining of them has already 

 been commenced. The depth of the mines is about 120 fathoms. 

 The work is under the superintendence of Mr. Harvey, the chief 

 engineer employed in draining the Haarlem Lake in Holland. Lon- 

 don Atlienccum. 



CONNECTICUT COPPER MINES. 



THESE mines, which are situated near Bristol, have been known for 

 some time, but they have of late excited much interest among capital- 

 ists and scientific men. and there are now over 300 men at work in 

 them. Prof. Silliman is of the opinion that they extend over thirty 

 miles south of Bristol, and that if thoroughly worked they would give 

 employment to 30,000 miners, while many others consider that they 

 can be made the most profitable mines in the United States. Farmer 

 and Mechanic. 



Another extensive copper mine has just been opened at Litchfield, 

 South Farms. Prof. Hubbard of Yale College has examined the 

 mine and made a highly favorable report of its value and location. 

 We understand that the developments thus far made show this mine 



