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the head, "Quaternary Geology." The economic products of the 

 county which are discussed are building stone, hydraulic cement rock, 

 clays, sand, gravel and natural gas. In connection with the discussion 

 of these products many valuable statistics are given and a considerable 

 amount of space is devoted to the records of wells which have been 

 sunk for natural gas in and about Buffalo. 



6. Geology of Orange County. By H. Ries. Pp. 393-475, plates 

 I-XLII, with one geological map. In this report the physiography 

 and topography and the stratigraphic, structural and economic geol- 

 ogy are ably discussed in detail. The formations present extend from 

 the pre-Cambrian gneiss at the base of the section to the Chemung 

 group at the summit. The economic products described are road 

 materials, brick clays, limestone, lead ore, building stone, flagstone, 

 and iron ores, besides the soils, mineral springs, water power and water 

 supply. 



7. Report on the Crystalline Rocks of St. Lawrence County. By C. 

 H. Smyth, Jr. Pp. 477-497. The principal purpose of the investiga- 

 tion described in this paper was to determine the distribution of the 

 crystalline limestones, and to collect data bearing upon the question 

 of the origin of the gneisses and the relation existing between these 

 rocks and the limestones. 



8. Report on the Geology of Clinton County. By H. P. Gushing. 

 Pp. 499-573, plates I-V. This paper discusses the topography and 

 general geology of the region, after which each township is treated 

 separately. The rock series discussed are, (1) gneissic series ; (2) lime- 

 stone series ; (3) gabbro series ; (4) Paleozoic series, extending from 

 the Potsdam sandstone to the Utica slate ; (5) dike series ; (6) pleisto- 

 cene deposits. 



9. Preliminary Report on the Geology of Essex County. By J. F. 

 Kemp. Pp. 575-614, plates I— XII. This is a continuation of the 

 report by the same author in the 1893 report, and the townships not 

 previously described are taken up for special consideration and the 

 areal geology of each is described so far as it has been determined. 

 Special notice is taken of economic products, namely, of iron ores. 



10. Sections and Thickness of the Lower Silurian Formations on 

 West Canada Creek and in the Mohawk Valley. By C. S. Prosser 

 and E. R. Cummings. Pp. 615-659, plates T— XII. The writers here 

 consider the Ordovician rock sections exposed in the gorge of the West 

 Canada Creek at Trenton Falls, at Newport and at Little Falls. These 



