ONONDAGA COUNTY. 
279 
feet, is as yet unproductive of any valuable mineral. The greater part of the surface portion 
of Onondaga lake is excavated in the red shale, the lower part of the whole of it extending 
considerably into its mass. Such also must be the case with Sodom lake, from its depth of 
one hundred and sixty-eight feet. 
The space occupied by the gypseous portion of the deposit, is from about three to four 
miles broad; the villages of Hartsville, Fayetteville, Orville, Camillus and Elbridge being 
placed near the line of its centre. Within the space containing the gypseous masses, we find 
the whole of the porous or vermicular limestone, the salt cavities or hoppers, and the fibrous 
cavities caused by sulphate of magnesia. Very little gypsum is quarried at the west end of the 
county, the quarries being opened chiefly in the towns of Manlius and De Witt; not that the 
west part is not productive in this mineral, the grading of the railroad along Nine-mile creek 
proving it to be equally if not more so than the east end. From the great size of the masses 
upon Cayuga lake near Springport, the quantity of gypsum is either greater west, which no 
fact noticed in the fourth district proves; or what is more probable, the maximum quantity 
is to the south of its northern outcrop. Should such be the case, from the association of rock 
salt with gypsum, any boring for the former, independent of the facts heretofore made known, 
should be south, and in accordance with the range of the greatest deposit of plaster. 
The porous or vermicular limestone is greatest in amount in this district, forming two 
distinct deposits: the upper, which is the same with that in Madison county, the average 
thickness of which is about four feet. In that county it appears to be continuous as to mass, 
as well as holding the same position. In Onondaga, no attempt was made to ascertain if it is 
continuous or not; but its position is fixed, being placed above the first series of plaster masses, 
and above the hopper cavities. It is well exposed in the hill at the Foot-street road near 
Syracuse, and also on the road which leads from the turnpike to Bellisle ; but better on Nine- 
mile creek, between the turnpike and the embankment, in the hill-side above the railroad. 
The pores of the upper mass are generally large, though also small; in which latter case, 
they are not to be distinguished from those of the lower, the material being the same in com¬ 
position and color. 
The lower mass, at the two localities where it is best exhibited, is about twenty feet thick, 
its pores small and color brown, though it is likely that this color in both masses is the effect 
of alteration, its porous nature readily admitting of a change even though not exposed to the 
surface, and its original color appearing to have been a dark blue. On the road from the 
turnpike to Bellisle, the interposed masses to the two porous rocks are similar to those below 
the upper one in Madison, and contains also the same fossil shells as at Bull’s quarry. 
At Syracuse, in the Foot-street road, the thickness of the lower porous rock is about the 
same; some of the intervening parts are also of the same kind with those of the former loca¬ 
lities, but with other products having a crystalline character, being serpentines ; the action of 
crystallization having operated powerfully, though locally, producing mica and even nodules 
of granite, or rather sienite. It is not necessary to suppose that any great degree of heat has 
here existed to produce these bodies ; nothing more being required, than that their elements 
