86 TRANSACTIONS OF THE [jAN. 31, 



tains a continuous supply throughout the year of 200,000 gallons 

 per day. 



There is no doubt that Mr. Macy has thus discovered a prac- 

 tical method of obtaining water in Arizona, which may be re- 

 peated in many parts of that territory, and which will be found 

 applicable in many other regions heretofore supposed to be prac- 

 tically deprived of water. 



There is now, at least, abundant experience to encourage the 

 search for and use of subterranean water for the most important 

 uses of life, in the shallow and loosely compacted deposits which 

 cover plains and valleys. Another significant example is found 

 in the new water-supply for the villages on the east shore of 

 Staten Island. A large part of this island is known to be cov- 

 ered with drift. That portion which is embraced between the 

 principal ridge of serpentine rocks running through the middle 

 of the island from north to south, and the dike of basaltic rock 

 which skirts the western shore of the island, both of which 

 have been des.cribed by Dr. Britton before the Academy/ 

 is especially to be noted as bearing water ; a very large 

 part of the rainfall, doubtless, because the whole area of eight 

 or ten square miles is peculiarly devoid of surface streams. 



Along the southwestern shore of the island there are unmis- 

 takable indications that the underground flow reaches the sur- 

 face only a few feet above high-water mark. Here the Crystal 

 Water Co. have sunk large tubes about 40 feet into the drift. 

 From these tubes the water destined for the villages along the 

 eastern shore of the island is pumped to a reservoir, 3|- miles 

 distant, situated on the top of the dividing ridge referred to, 

 whence it descends through pipes by gravity about 2^ miles fur- 

 ther to the eastern shore, furnishing a head of about 250 feet. 



A few years ago Staten Island and Long Island were supposed 

 to be almost destitute of water, when the prospective wants of 

 their large and increasing population were considered. Now it 

 may be said that in this respect, though isolated from the main 

 land, they are better off in many respects than New York City. 

 I recently examined, at the request of the Trustees of the village 



* ' The Geology of Richmond Co., N. Y., Annals N. Y. Ac. Sci., Vol. 11. 



