248 OXYGEN. 



cubic inches of it dissolve three and a half cubic inches of this 

 gas. 



If a lighted wax taper attached to a copper wire be blown 

 out, and dipped into a vessel of oxygen gas, while the wick 

 remains red hot, it instantly rekindles with a slight explosion, 

 and burns with great brilliancy. If soon withdrawn and blown 

 out, it may be revived again in the same manner, and the 

 experiment be repeated several times in the same gas. Lighted 

 tinder burns with flame in oxygen, and red-hot charcoal with 

 brilliant scintillations. Burning sulphur introduced into this gas 

 in a little hemispherical cup of iron-plate with a wire attached 

 to it, burns with an azure blue flame of considerable intensity. 

 Phosphorus introduced into oxygen in the same manner, burns 

 with a dazzling light of the greatest splendour, particularly 

 after the phosphorus boils and rises through the gas in vapour. 

 Indeed all bodies which burn in air, burn with increased vi- 

 vacity in oxygen gas. Even iron wire may be burned in this 

 gas. For this purpose thin harpsichord wire should be coiled 

 about a cylindrical rod into a spiral form. The rod being with- 

 drawn, a piece of thread must be twisted about one end of the 

 wire, and dipped into melted sulphur; the other end of the 

 wire is to be fixed into a cork, so that the spiral may hang 

 vertically. The sulphured end is then to be lighted, and the 

 wire suspended in a jar of oxygen, open at the bottom, such as 

 that represented in Fig. page 246, supported upon an earthenware 

 plate. The wire is kindled by the sulphur, and burns with an 

 intense white light, throwing out a number of sparks, or oc- 

 casionally allowing a globule of fused oxide to fall ; while the 

 wire itself continues to fuse and burn till it is entirely con- 

 sumed, or the oxygen is exhausted. This experiment forms 

 one of the most beautiful and brilliant in chemistry. The 

 globules of fused oxide are of so elevated a temperature, that 

 they remain red-hot for some time under the surface of water, 

 and fuse deeply into the substance of the stoneware plate upon 

 which they fall. 



Oxygen gas is respirable, and indeed is constantly taken 

 into the lungs from the atmosphere in ordinary respiration. 

 When a portion of dark blood drawn from a vein is agitated 

 with this gas, the colour becomes of a fine vermilion red. The 

 same change occurs in the blood of living animals, during respi- 

 ration, from the absorption of oxygen gas, which is believed 



