OTSEGO COUNTY. 353 



The Vlie, or natural meadows, are numerous in many parts of the district : they are the 

 prairies of the west upon a small scale. Their soil, being composed of minutely divided parts 

 or fine earth, is favorable for grass, the rapid growth of which smothers the germinating tree. 

 This is the primary cause why trees do not exist where grass is rank ; the others are but 

 subordinate ones. One and all in the district show the same origin, having been ponds or 

 lakes receiving the wash of the country which they drained, the finer particles of which being 

 diffused through their waters, have, by subsidence, formed their level bottom, and their highly 

 productive soil for grass. 



2. Otsego County. 



The surface of the whole of Otsego county consists of high broad ridges, having generally 

 a common south and west direction, their sides rounded, and separated by long, deep and 

 usually broad valleys. The northeast comer of the county terminates abruptly towards the 

 Mohawk river, presenting a succession of cUfis, being the continuation of the Helderberg 

 mountain of Albany county. 



The northeastern part of the county presents the series of limestone, etc. which forms the 

 Helderberg division. This division passes through the upper parts of the towns of Cherry- 

 Valley and Springfield, resting upon the Frankfort slate and its sandstone, these latter consti- 

 tuting the larger part of the upper member of the Champlain division. No part whatever of 

 the Ontario division exists at the extreme east end of the county. It commences not far west of 

 the road which leads from Cherry- Valley to Fort-Plain, showing the Oneida conglomerate and 

 the Clinton group, and these two masses are continuous from thence to the west of Rochester. 



From the southwest dip of all the rocks of the county, their highest point is towards where 

 the Helderberg range or cliff joins Schoharie county ; and from that point, they all decline to 

 the southwest, rising one above the other. 



The whole of the limestone of the county is confined to the Helderberg division, and there- 

 fore is found only in the range of the northern ends of the towns of Cherry- Valley and Spring- 

 field, and the extreme northwest comer.of Richfield. It is the most valuable part of the county 

 for its mineral products ; lime being an essential element in all buildings for the use of man, 

 all important for the improvement of soil, and requisite for a whitewash where cleanliness and 

 sweetness are required. 



The Helderberg division exhibits two portions of the Onondaga salt group : The first or 

 lowest is the calcareous shaly part, from whence the sulphur springs to the north of Cherry- 

 Valley issue ; and the second, the harder and more calcareous part, in thin regular layers, which 

 overhe the first part. On the top of the latter mass is the Water-lime group ; above it is the 

 Pentamerus limestone, showing three divisions ; then the Catskill shaly limestone ; next above, 

 the Cauda-galli grit ; the Onondaga limestone, or the marble rock of the valley, then follows ; 

 and finally the Corniferous limestone, the latter rock showing that its surface was an ancient 

 river or valley bottom, being the upper mass of the division. Neither the Oriskany sandstone 

 nor the Schoharie grit were seen in place, though doubtless both exist in the county. 



