HYDROLOGY OF NEW YORK 



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of the Conglomerate group of the Carboniferous. The main Mus- 

 kingum river flows generally from north to south, with its main 

 branches to the east and west, that to the west going a short dis- 

 tance into the Waverly group, which is chiefly sandstone and 

 shale, a subdivision of the Carboniferous. The dip is from north 

 to south. In view of the extremely low runoff of this stream, it 

 seems tolerably evident that there can be no material contribution 

 by percolation through these strata. 



As other examples of underground flow, the writer may men- 

 tion Toyah creek, in Texas, where a stream of (his recollection is) 

 10 or 50 cubic feet per second flows from the base of a mountain 

 with no indication as to its source. The well-known streams in 

 Mammoth and Luray caves are doubtless familiar to all. There 

 are also a number of river channels in the west where the water 

 sinks into the porous soils, to reappear at some point lower down ; 

 but these are hardly allied to the cases under consideration, 

 because the source is here visible. 



A stream at Lausanne, Switzerland, may also be mentioned. In 

 1872 there was a serious epidemic of typhoid fever at Lausanne, 

 Switzerland, which, on investigation, was found to proceed from 

 a brook* irrigating lands about a mile distant from a public well, 

 from which the 800 inhabitants of the village mostly took their 

 water supply. Ten years before, or in 1862, a hole had appeared 

 in the channel of the brook at a certain point, 8 feet deep and 3 

 feet wide, which disclosed at its bottom a running stream, appar- 

 ently fed by the brook from a point higher up. The brook itself 

 was led into this hole, with the result that the water all disap- 

 peared and in an hour or two streamed out at the public well, 

 showing a connection which had been suspected for years. On 

 refilling the hole the brook returned to its bed. 



After the epidemic had ceased in 1872 an investigation was 

 held, the hole was reopened and a large quantity of salt thrown 

 in; its presence in the public well was easily ascertained by a 

 chemical examination. 



This case discloses some points of interest. Here was a con- 

 siderable stream flowing underground which was easily increased 



