Calculatory

[Lat. calculator i us.] Belonging to calculation. Cal'culous, a. [Lat. calculosus.] Stony; gritty; hard, like stone Phosphide of C. is a compound interesting as the source of the phosphides of hydrogen. It is prepared by distilling phosphorus over lime heated to a low redne , a mixture of phosphide of lime and phosphate of calcium being the result. Phosphide of calcium is a dull red substance, hard enough to strike fire with steel. When powdered and exposed to the air, it slacks, emitting phosphuretted hydrogen In its unslacked form, it is decomposed when thrown into water, phosphuretted hydrogen being evolved, which ignites spontaneously. Form. CaP. Sulphides of C. There are several compounds of C. with sulphur, the principal of which are the pro to sulphide, which is known by the name of Canton's phosphorus, and the pent a sulphide. Calcographer, n. A practiser of calcography. Calcograph'ic, Calcograph'ical, a. Pertaining to calcography. Calcography, n . [Lat. calz , chalk, and Gr. graphein , to write.] The art of drawing with chalk, or of engraving after that style.