TRACT 37.

OF GTJNNKRT.

303

duces the explosion. But of the whole mass of 8 parts,is equal to of the 6 parts or nitre ; that is, -£ s or \ of thenitre consists of condensed air, or the weight of the air is tothe weight of the gross matter in the nitre, as 4 to G, or as 2to 3; and these two parts it is probable are of equal densityor specific gravity. But the specific gravity of nitre is 1900,that of water being 1000, and of air 1*2, which is containedin 1900, as much as 1583 times; that is, the air in the nitremust be condensed the amazing quantity of 1583 times, if itsspecific gravity be equal to the compound nitre itself!

179. The condensation of the air, in the solid nitre, maybe otherwise determined thus. The weights of the threesolid ingredients, nitre, sulphur, and charcoal, being as thenumbers 6, 1, 1, and their specific gravities respectively1900, 1810, and 400 nearly, water being 1000, or they areas 19 and 18 and 4 nearly, when water is 10. Therefore themagnitudes of these ingredients are as T ft 7 , T ^, a, or as thenumbers 216, 38, 171, when brought to a common denomi-nator 6S4. The first fraction is nearly equal to the sumof the other two and that is, the magnitude of thenitre in the compound, is -J. of the whole magnitude. Butthe condensed air is * of the nitre ; and | of •?- = ■£; thereforethe magnitude of the air is of the wdiole, considering themall as in a solid mass. But now the specific gravity of thismass will be found by dividing the wmight 8, by the iriagni-

gravity of the solid mass, while that of the same when grainedas powder for use, is only 9-3“ ; then as 937 : 128 : : 236(the density of the elastic fluid when occupying the space ofthe grained powder) : 322 the density of the same in thespace of the solid. But the space occupied by the fluid is-|.of the wdiole: therefore 322 x 5 1610 is the condensa-

tion of the same, or the number of times it is denser thancommon atmospheric air, and is nearly the same as beforefound by the other method. That is, the air is condensed inthe nitre, about 1600 times, nearly double the density.of

tude

_ 425

that is Sq-A-f.! = 12-8 is the specific