REPORT OF THE DIRECTOR I916 301 



of cutting and dressing trap is also an obstacle to its employment 

 for building or ornamental purposes. 



The largest body of trap in New York State is represented in 

 the Palisades of the Hudson, and the continuation of the same 

 intrusion is found southward in New Jersey and on Staten island. 

 This occurrence, properly, is diabase, with plagioclase, feldspar 

 and pyroxene as the main ingredients. The Palisades are the 

 exposed edge of a great sill or sheet of the rock which came up 

 from below and forced its way along the bedding planes of the 

 Triassic sandstones and shales. The sheet is several hundred feet 

 thick, in places nearly iooo feet, but the outcrop is narrow, seldom 

 over a mile wide and in places is limited to a single vertical escarp- 

 ment. The principal quarries are near Nyack and Haverstraw at 

 the base of the cliffs. Other quarries have been opened near Suf- 

 fern, on an isolated intrusion of a similar rock, and also near Port 

 Richmond, Staten island, at the southern end of the Palisades sill. 



There are numerous occurrences of trap in the Adirondacks, 

 where it occurs in the form of dikes that intersect the older Pre- 

 cambrian crystalline formations. The dikes occur literally in thou- 

 sands in Essex and Clinton counties, but they seldom attain any 

 considerable thickness, 20 to 30 feet being about the maximum. 

 Near Greenfield, Saratoga county, and at Little Falls, Herkimer 

 county, occur dikes of much larger size. The Greenfield dike has 

 been worked in years past for crushed stone. 



The output of trap in 1916 was valued at $956,100, a large gain 

 over the total of $550,960 reported in the preceding year. The 

 quantity of crushed stone reported was 1,280,500 tons, consisting 

 of crushed stone for roads 561,000 tons, for railroad ballast 64,250 

 tons, and for concrete 655,250 tons. In 191 5 the quantity was 

 reported in cubic yards and amounted to 683,700, a yard amounting 

 to nearly one and one-half tons. 



TALC 



The conditions in the talc trade showed notable improvement in 

 1 91 6 and more than made up for the dulness of the preceding 

 season. The demand in the paper trade was especially active, with 

 the curtailment in the supply of foreign clays which used to enter 

 the market very freely. In their place southern clays are being 

 employed quite extensively, but not in the full proportion to the 

 former use of foreign material. While the paper industry, especi- 

 ally the branches engaged in book and writing paper manufacture, 



