In speaking farther of the compounds of nitrogen with oxygen, we will limit ourselves to the monoxide, or laughing gas. This is now used as an anæsthetic in dentistry, etc., and is quite successful, as a rule. People afflicted with heart disease should not use it without advice, however. When inhaled into the lungs it makes the subject very hilarious, and the effect is rather noisy. It is obtained from the nitrate of ammonia, which, on the application of heat, decomposes into nitrous oxide and vapour. Warm water should be used for the trough. The gas is a powerful supporter of combustion.
Fig. 353.—Cavendish’s experiment.
Binoxide of nitrogen is of importance in the manufacture of sulphuric acid.
Fig. 354.—Experiment to obtain nitric acid.
Nitrogen combines with hydrogen, forming various compounds. These are the “amines,” also ammonia, and ammonium. Ammonia possesses the properties of a base. Its name is derived from Jupiter Ammon, near whose temple it was prepared, from camels’ dung. But bodies containing nitrogen give off ammonia in course of distilling, and hartshorn is the term applied to horn-cuttings, which yield ammonia, which is a colourless gas of strong odour and taste now obtained from gas-works.
Fig. 355.—Apparatus for obtaining laughing-gas.