8 



NEW YORK STATE MUSEUM 



2,400,000 tons, while the actual output in the period 1 889-1 908 has 

 been 2,063,995 tons. The combined total in round numbers is 

 4,464,000 tons. 



The production and imports of gypsum for the United States 

 during the period 1890-1908 aie given in the table herewith. 



A comparison of the statistics in the two tables shows that New 

 York has held its place in the general industry of the country which 

 has increased its output over 800 per cent since 1890. The local 

 output in 1908 was approximately 18 per cent of that recorded for 

 the United States in the same year. There is little doubt that the 

 use of gypsum in this country will continue to expand during the 

 immiediate future, though most likely at a slower rate than that 

 exhibited in the last few years. 



Production and imports of gypsum for the United States 





PRODUCTION a 



IMPORTS 6 





Short tons 



Value 



Short tons 



Value 



i8go 



182T995 

 208 126 



2561259 

 253 615 

 239 312 

 265 503 

 224 254 

 288 982 

 291 638 

 486 235 



594 462 



633 791 



816 478 



I 041 704 



940 917 



I 043 202 



I 540 585 



I 751 748 



I 721 829 



$574 523 

 628 051 



695 492 



696 615 

 761 719 

 797 447 

 573 344 

 755 864 

 755 280 



I 287 080 

 I 627 203 



1 50^6 641 



2 089 341 



3 792 943 



2 748 325 



3 029 227 



3 837 975 



4 942 264 

 4 138 560 



178 857 

 119 817 

 187 936 

 167 663 



164 527 

 195 844 

 183 561 



165 865 

 169 039 

 199 844 

 212 990 

 238 310 

 309 014 

 269 484 

 297 516 

 403 119 

 440 586 

 445 890 

 302 047 



$229 859 

 226 3^9 

 308 oil 

 211 924 

 196 060 

 237 231 

 215 526 



195 714 

 199 865 

 239 853 

 249 057 

 258 067 

 208 167 

 324 163 

 332 582 

 423 204 

 487 546 

 499 030 

 327 627 



1891 



1892 



180^ 



1894 



i8qs; 



i8g6 



t8q7 



1898 



1899 



1900 



IQOI 



1902 



1903 



IQO5 



1906 



1007 



IQ08 







a The figures of production are based on the crude gypsum, while the values are for the 

 marketable products. 



b Includes crude and calcined gypsum, but not manufactured plaster of paris. 



COMPOSITION AND CHARACTERS OF GYPSUM 

 Chemical and mineralogic characters. Gypsum is a hydrated 

 ■calcium sulfate with the formula CaSO^. 2H2O. Its ideal composi- 

 tion is represented by the following percentages by weight: lime 



