442 PROF. EMMONS' VIEWS. 



stone and the Taconic slate, near a church three miles east of Whitehall, in a deep ravine. 

 The sandstones dip 5 or 6E., and the slate 30 or 40E. 



Passing into Vermont there are three localities of special interest, showing the junction 

 of the Taconic rocks with the Potsdam sandstone and the calciferous sandstone, viz., in 

 Orwell, Snake Mountain and Highgate Falls. The discovery of ConocepTialus in Highgate 

 as long ago as 1847, by Prof. Adams, and the primordial fauna at Point Levi, in Canada, 

 ought surely to convince all, that the red sandrock series is equivalent to the Potsdam 

 sandstone and calciferous sandstone. 



In going from Mount Independence, to a little east of Orwell village, the following is 

 the order of rocks passed over: Calciferous sandstone, Trenton limestone, calciferous 

 sandstone, black slate and sparry limestone, all dipping east. Consequently there must 

 be two fractures, one to bring up the calciferous sandstone above the Trenton limestone, 

 and another to elevate the Taconic above the level of the Silurian rocks. Prof. Emmons 

 has given a figure and description* of this section, the latter of which we will quote : 



" With only a superficial examination, they [these three limestones] would be regarded as one rock, 

 belonging to the same period. On a careful examination, however, it is clear that the eastern mass rests 

 on a greenish slate, and by going east a short distance, it is plain enough that a slate also overlies it [the 

 most eastern limestone, or sparry limestone], so that it is inclosed between beds of slate, and in this 

 respect is similar to the limestone which lies in the tunnel of the Western Railroad near the State line 

 [Mass.], and which belongs to the slate group, as is clearly proved by observation. Having determined that 

 the eastern limestone at Orwell lies between beds of slate, our convictions it seems should be, that it is not 

 lower Silurian, nor Trenton, nor either of the masses into which the lower Silurian limestones have been 

 divided. But what is the limestone on which the village is built ? To determine this question, I traced it 

 northward, keeping it in view for a few miles, and then turned directly west towards the lake. On passing 

 over two or three rocky terraces composed of this rock, I came directly upon the Potsdam sandstone which 

 cropped out from beneath this silicious limestone, and over which I had passed, and which 1 had traced 

 from Orwell. The result of this examination proved that the rock at Orwell, which seemed to join on 

 to the sparry limestone between the slates, is the calciferous sandstone. The two limestones might there- 

 fore be confounded, but, without the aid of a fossil, the geological formation to which the calciferous 

 sandstone belongs is proved by simply determining its relations, and at the same time it is also proved 

 that another limestone of a different period cropped out very near it, and might have been confounded with 

 it. It proves, too, the fallacy of the doctrine that the lower Taconic rocks, or the lower limestones, are 

 but altered Silurian : we have two limestones of different ages together one rests on the Potsdam 

 sandstone, and is of the Silurian age ; the other on slate, and belongs to the Taconic system. The theory 

 of plications and folds it will be seen, will not explain the phenomena or the facts. It is not even a 

 plausible hypothesis, when offered in explanation of the phenomena I have related. I have been unable 

 yet to detect fossilsf in the sparry limestone of Orwell, but its condition is as favorable for their existence 

 as in the calciferous sandstone. This locality proving the existence of a limestone which cannot be placed 

 in coordination with any of the limestones of the lower Silurian, throws the burden of proving the period 

 to which it belongs on other shoulders, provided it does not belong to the Taconic system." 



Prof. Emmons thinks that there are "four dislocations on this section; and the order of arrangement, 

 beginning with the limestones, is such that we pass, by successive steps, from the oldest to the newest, 

 terminating with those on the lake." 



*American Geology, Part II, pages 83, 84. 

 f Obscure specimens of Slromatopora, ductetes, and encrinal stems have since been found in it. C. H. H. 



