All About Inventions and Discoveries
The Romance of modern scientific and mechanical Achievements

CHAPTER XII Living on the Air During the sixth decade of the eighteenth century a British scientist, whose name to-day is one of the most famous throughout the world of investigation and discovery, was living the life of a recluse in a grand old house upon the outskirts of London. Quietly and undisturbed he pursued his one hobby— science—throughout the livelong day. One line of experiment and research which had been prosecuted industriously and untiringly for many years culmin- ated in a sensational discovery. This was the separa- tion of hydrogen, the lightest gas which is known, and its definite resolution into one of the elements. Henry Cavendish, the scientist toiling in solitude, went farther. He ascertained that the newly- found gas was combustible, and that when burned in the free atmosphere which we breathe, it seized the oxygen, and as a result of the chemical action which ensued was transformed into water. As we all know, the atmosphere which surrounds this globe and is essential to our existence is composed of two elements—oxygen and nitrogen. Moreover, we realise that the proportion of these two constituents must be one of the former to four of the latter to enable our lungs to perform their functions smoothly and quietly as designed by Nature. Nitrogen, how- 262