CORTLAND COUNTY. 291 



North of Homer, also, are the quarries of Bishop, Barrow, &c. In a ravine on the west 

 side of the valley, about three miles to the north of the village, in which is the saw-mill of 

 Mr. Hotchkiss, there is upwards of fifty feet of shale and sandstone exposed ; the shale greatly 

 predominating, and the whole of a dark grey color. 



The last quarry noticed in the valley was Harris', about a mile south of Preble. It fur- 

 nishes good building stone, and contains the same vegetable impressions found near Homer. 



Chemung group. This group covers the southwest part of Virgil, being the highest land 

 of the county. Not much rock is exposed, the quarries opened being principally for field 

 enclosures. The same group appears to exist also where the towns of Marathon and Willet, 

 Freetown and Cincinnatus, join each other. It is the terminal mass of the county, and ex- 

 tends south beyond the Susquehannah river. 



The valley in which the villages of Cortland, Homer and Preble are seated, is broad and 

 level, filled to an unknown depth with alluvion, showing in many places that no small part of 

 its mass are the rolled stones of the rocks to the north of the Limestone range. The valley 

 resembles, in most of its features, the parallel one in Madison, through which the Chenango 

 canal passes, and shows a like origin ; the difference being that the one was excavated in the 

 Hamilton, the other in the Portage and Ithaca groups. 



Ponds or lakes are also alike common to both valleys, being the deeper points which were 

 left when the waters were drained from their surface. These ponds have also the same lake 

 marl deposits, and derived equally from the same materials, the calcareous alluvion of the 

 northern region, which extends through all the southern valleys. A chain of these lakes ex- 

 tends from those near Tully, through Preble, to the north part of the town of Homer. They 

 contain marl, but no use has as yet been made of it. 



Another and small cluster of marl lakes or ponds exists to the southwest of Cortland village. 

 These ponds are three in number : Crandall's covers an area of fifteen acres ; Swain's, six 

 acres ; and Chatterdon's, four acres : they are near to each other, and connected together. The 

 marl is partly of an ash color when recently taken out, owing to vegetable matter, but whitens 

 by exposure to the air. The marl, with the exception of the small quantity of vegetable 

 matter, being a pure carbonate of lime, when properly burnt, it makes the best of lime. A 

 considerable number of bushels of lime are here annually burnt : the marl is dug, partially 

 dried, moulded into bricks, and then thoroughly dried and burnt. 



From the abundance of aquatic plants in the ponds, and from their being more or less 

 covered with marl, an idea exists that they originate it ; whereas they are but points of attrac- 

 tion, to which the marl adheres in separating from its solvent. The ponds are seated in allu- 

 vion, from which the calcareous material has been derived which covers their bottom. The 

 greatest known thickness of any of these deposits of marl is about twenty feet. 



