REVIEW OP AUTHORITIES. Ill 



vania and Ohio," section no. ix). On a section crossing the Catskill 

 range from Schenevus to Glasco, prepared by Professor James Hall, it 

 was shown that the " Portage and Chemung have a thickness of more 

 than 2,000 feet" for that region (ibid., vol. xxiv, B, 1876, p. 82). 



B. — Prosser noted: "Black argillaceous shales 20 feet in thickness 

 near Smyrna [in the Chenango valley, in the northern part of Chenango 

 county "] (ibid., vol. xxxvi, 1887, p. 210). 



C. — Prosser reported : " Limestone layers, separated by calcareous 

 shales, with a total thickness of 25 feet . . . near Upperville, in 

 Smyrna township." At least part of this series belongs to the Tully 

 limestone (ibid., p. 210;. Emmons said: "In Albany and Schoharie 

 counties it [Tully limestone] is unknown. . . . The thickness . . . 

 is from 12 to 15 feet " (Agriculture of N. Y., vol. i, 1846, p. 186). 



D. — Professor Hall wrote : " The thickness of this group [Hamilton] 

 on the eastern limit of the district [fourth geological district, Cayuga 

 lake region] cannot be less than 1,000 feet" (Geol. N. Y., pt. iv, 1843, p. 

 194). Vanuxem said: "The group is of great thickness; in no part 

 probably less than 300, and swelling to 700 feet" (Geol. N. Y., pt. iii, 

 1842, p. 151). Professor Dana stated that " the greatest thickness — about 

 1,200 feet — is found east of the center of the state" (Manual Geology, 3d 

 ed., p. 266) ; but it is also stated that " the Hamilton strata are 1,000 feet 

 thick in central New York" (ibid., p. 267). While Professor Hall said, 

 " The thickness of this group [Hamilton] along the Schoharie creek is 

 much greater than has been supposed, amounting probably to 3,500 feet " 

 (Proc. Albany Institute, vol. 1, 1871, p. 133). 1,100 feet seems to be a fair 

 average for this section, based upon Hall's estimate for Cayuga lake and 

 Dana's for eastern central New York. Emmons stated: "By estimating 

 the fossiliferous and non-fossiliferous parts by themselves and summing 

 up the result, we obtain from 1,000 to 1,200 feet thickness. In Albany 

 and Schoharie counties the thickness appears to be much greater than 

 in the western counties " (Agri. of N. Y., p. 185). 



E. — Vanuxem wrote : " Near Marcellus and in other parts of Onondaga 

 where best observed they show no fossils for one or two hundred or more 

 feet where thickest" (Geol. N. Y., pt. iii, p. 147); also, "A boring of 100 

 feet for coal was made in the Marcellus shales by Mr Sage near the road 

 from Chittenango to Cazenovia" [Madison county] (ibid., p. 149); and 

 Dana states that " The Marcellus shale rarely exceeds in thickness 50 

 feet" (Manual Geol., 3d. ed., p. 267). Emmons stated: " It is probably 

 less than 100 feet at Schoharie and Manlius " (Agri. of N. Y., p. 183). 



F. — Vanuxem said: "The Corniferous limestone is at its maximum 

 thickness in the village of Cherry Valley [Otsego county], where it is 

 probably from 60 to 80 feet thick" (Geol. N. Y., pt. iii, p. 141) ; while 



