Notice of the Louisville Canal, fyc. 69 



The second rock is a black bituminous slate. It overlies 

 the limerock above described, and forms the banks of the 

 river, as far down as I have been (ten miles) ; and is seen in 

 the bottom and banks of the numerous creeks, which enter 

 the river from the north. This rock is said to be the same 

 as that found at Pittsburg overlying the coal ; it is there- 

 fore expected that coal will be found under it here. But 

 boring has been tried near New Albany, three hundred feet 

 deep, without finding either coal or salt. A spring that 

 comes through this slate rock, near where the boring was 

 made, contains a considerable quantity of sulphuretted hy- 

 drogen gas, and this gas is continually rising through the 

 water of the spring. The smell of this gas is perceived at 

 some distance from the spring. I have seen no petrifactions 

 in the slate rock. It sometimes contains small masses of 

 sulphuret of iron, disseminated through it. The limerock 

 above mentioned, with occasional patches of this slate, is the 

 rock to be excavated in the construction of the canal. 



The third rock in order, is the sand rock. It is of a yellow- 

 ish, and sometimes a blue color. It has a compact texture, 

 and a laminated structure. It forms the hilly country west 

 of the rapids, called the Knobs j and from one of these hills, 

 the stone for the face of the lock walls is quarried. It con- 

 tains but few petrifactions. The minerals are quartz crystals 

 of a yellowish color, calcspar and sulphate of magnesia ; this 

 salt, in a state of efflorescence, may be seen coating some 

 of the stone brought here for the locks. This sandrock is, 

 in some of the highest knobs, overlayed by another limerock. 

 At the quarry this limerock is about twenty feet thick. This 

 makes the fourth rock, which I have mentioned. 



The alluvion about the canal is chiefly blue and yellow 

 clay, mixed with fine sand and gravel. It contains half de- 

 cayed logs, bones of quadrupeds, &c. and occasionally prim- 

 itive masses — all of which seem to indicate that the river had 

 once run near where the canal now does. 



Should you think any part of this communication worthy 

 of a place in the American Journal of Science, it is at your 

 service. 



Besides the drawings of the river, &c. I send a geological 

 profile from Louisville to the knobs, a profile of the canal, 

 and a plan of the locks. 



Shippingsport, Nov. 10, 1827. 



