and Geology of Lake Ontario. 271 



passing into each other) in very slightly concave layers of vast 

 extent, but of comparatively small thickness. It is almost cer- 

 tain that they underlie the lake itself. On the north shore, al- 

 though the salt formations have never yet been seen, numerous 

 springs of brine sufficiently attest their presence. 



In describing these rocks, I shall begin by stating by them- 

 selves the results of Mr. Eaton's researches, which have been 

 much more minute than mine, on the middle and upper por- 

 tions of the series. I shall then describe the rocks incumbent 

 on the gneiss at the north-east end of the lake and in its outlet, 

 which differ from their equivalents in the Macomb Mountains, 

 as detailed by Mr. Eaton. 



Rocks of the South Side of Lake Ontario. 

 The gneiss has been described. — Inclining upon it, Mr. Eaton 

 found on the west side of the " Litde Falls* " a rock, which 

 he calls " calciferous sand-rock," or " transition calcsand." 

 He describes it as an aggregate of quartzose sand and fine 

 grains of carbonate of lime, in variable proportions, the quartz 

 generally predominating. On exposure, the calcareous part 

 soon disappears, leaving the surface a mere siliceous sand- 

 stone. It abounds in geodes, often lined with quartz crystals. 

 It is very irregular in its form and structure ; sometimes com- 

 pact, more commonly cellular, and full of druses. It contains 

 in small disseminated masses, or in geodes, anthracite-coal, 

 sulphurets of lead and zinc, green carbonate of copper, lamel- 

 lar barytesf. 



This rock, at the above-mentioned place "spreads out to a 

 considerable breadth. Six miles north of the canal it may be 

 seen passing under the limestone (carbonif.), a little west of 

 the ridge (of the Little Falls). Near West Canada Creek :f, 

 it emerges from beneath the same rock, towards the bottom of 

 a hill. It may then be seen forming the banks and bed of the 

 creek for several miles. It evidently leads away thence in a 

 north-west direction toward the outlet of Lake Ontario §." 



Until the country here be more cleared, and observations 

 be more multiplied, no very distinct idea can be furnished of 

 the form and extent of this rock. It is most probably a nar- 

 row band, whose length runs north, and at its west border 

 dipping under the next rock, the metalliferous rock of Eaton, 

 the carboniferous of Conybeare. Mr. Eaton only ailverts to 

 the stratification of the calciferous sand-rock, in mentioning 

 (as above) that it inclines upon the gneiss. He speaks of it as 



• 100 miles E. of Lake Ontario. | North of Utica. 



t Geological Survey, p. '62, $ Geological Survey, p. 76. 



common 



