HYDROLOGY OF NEW YORK 



717 



of this region, there are no natural water supplies to be found, 

 except in the elevated regions of the Allegheny water center, where 

 adequate supplies mar be made by storage. Many of the lakes are 

 not available, because they receive so much sewage as to render 

 the water unsafe without nitration. This remark applies to Lakes 

 Erie and Ontario and to the Niagara river. 



The preceding remark also applies in some degree to the region 

 east of Seneca lake and south of the Mohawk river. 



As to why this is so, it may be remarked in a few words that 

 the geology of the region is not favorable either to subterranean 

 water-supplies, or to large streams flowing on the surface. The 

 formations in an ascending order from Lake Ontario to the south 

 line of the State are Medina sandstone, Clinton sandstone and 

 limestone, Niagara shales and limestone, Salina shales and lime- 

 stone, the lower and upper Helderberg limestones. Hamilton 

 shales and sandstone, and Portage shales and sandstone. There 

 is also a small area of cretaceous clays and sands in Cattaraugus 

 and Allegany counties, near the south line of the State. None of 

 these formations is favorable for well supplies — the preferable 

 future water supplies of the entire region must be surface water, 

 and made by storage. 



INLAND WATERWAYS 



Trade and commerce of Hudson river. The importance of the 

 Hudson river as a great waterway of commerce is shown by Charles 

 G. Weir in a report made in 1890. Aside from its own local trade 

 the river absorbs all the traffic of the Erie, Champlain and Dela- 

 ware & Hudson canals, 1 besides the great coal trade of the Penn- 

 sylvania Coal Company at Xewburg and the Erie coal trade at 

 Piermont. The average season of navigation of the river is two 

 hundred and forty days. The two principal industries on the Hud- 

 son river, which add materially to the total tonnage, are ice and 

 brick. The capacity of the ice houses on and near the river 

 exceeds 4,000,000 tons, and the amount annually harvested is 

 about 3,500,000 tons. The bricks manufactured on the river 

 exceed 850,000,000. 



l The Delaware and Hudson canal lias been abandoned since the above 

 sentence was written. 



