300 NEW YORK STATE MUSEUM 



it reached over $2,000,000. An examination of the conditions year 

 by year shows that the industry has been depressed by the strong 

 competition it has had to meet from other kinds of material in the 

 building and city engineering markets. Granite and cement have 

 been gradually superseding sandstone for street work, and the 

 same holds true for building stone. 



Of the total returned for 1916, the bluestone quarries reported an 

 aggregate value of $376,845, against a value of $339,779 in the pre- 

 ceding year. The slight gain may doubtless be accounted for by 

 the high prices of cement that ruled during the year. The value of 

 the building stone included in the total was $168,834 against $178,- 

 577 in 191 5. Curb and flagstone amounted to $169,973, against 

 $155,288 in 191 5. Of other kinds, there was produced crushed 

 stone valued at %2j,y6y and miscellaneous kinds valued at $10,271. 

 The Hudson River district accounted for an aggregate of $98,669, 

 mostly curb and flagstone; the Delaware River district contributed 

 $67,493, made up largely of curb and flagstone but with some 

 building stone. 



The sandstone other than bluestone represented a value of 

 $337,713 as compared with $550,632 in 1915. Paving blocks were 

 the largest single item, with a value of $131,430, while crushed 

 stone was worth $96,788, building stone $16,137 and other kinds 

 $4284. Orleans county alone contributed a product worth $226,945, 

 which was little more than one-half of the value reported in 191 5, 

 in actual figures $449,620. 



TRAP 



Trap is not a distinct variety of rock, but the name is given col- 

 lectively to the fine-grained, igneous rocks that occur in intrusive 

 sheets and dikes. From granite it differs by its darker color, due 

 to the absence of quartz and the participation of the ferro- 

 magnesian minerals in large amounts. Some of the so-called 

 " black granites," however, are really trap. The particular value 

 of trap lies in its hardness, toughness and lack of cleavage. Its 

 fine, compact, closely knit texture gives the stone great wearing 

 powers, and it is eminently adapted for road metal and concrete of 

 which heavy service is required. The principal outlet, therefore, is 

 for crushed stone. It has been used to some extent, also, for paving 

 blocks, but these are rather difficult to prepare, since trap very 

 seldom shows any capacity for parting comparable to the rift and 

 grain structures of granites. As building stone it finds very little 

 application, probably on account of its somber color. The expense 



