A Manual of Useful Studies Author:Noah Webster Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: CHAPTER III. ; THE ATMOSPHERE. . .' ( The atmosphere is the fluid encompassing the globe, consisting of air, which contains water and other vapors. The ai... more »r is an elastic substance, being capable of great compression. It is invisible, inodorous, and colorless. It is compound substance, consisting of oxygen and azote, or nitrogen; about twenty-three parts of a hundred are oxygen ; the remainder nitrogen. Oxygen signifies, a generator of acids ; it is a gas which uniting with another substance fflrms an acid. Nitrogen is also a -gas, and the word signifies, a generator of niter. It is called also azote, which signifies, fatal to life. Oxygen is vitaiir, that part of air which is respirable, and is the support of animal life. It is also the support of combustion, or fire, and by itself produces intense heat. Nitrogen has opposite properties, for when inhaled into the lungs, it is instantly fatal to life. These facts 'exhibit a wonderful pheno- me'non ; that when these substances are combined, they form another substance with properties different from those of the constituent gases, and the existence of which is essential to all animal life upon land, and to the life .of many aquatic animals. Air is inhaled into the lungs by respiration, or breathing ; the . oxygen is separated from the nitrogen, and it is evidently the supporter of life, and the generator of heat in animal bodies. Air, in the atmosphere, is combined with water, or holds it in solution, and the atmosphere is the vehicle which convoys water over the earth. Hence the formation of clouds, from which proceed fain, snow, and hail. This is a most wonderful contrivance to receive aqueous particles, and transport them to every part of the earth; for supplying water to nourish plants and to accommodate mankind in ...« less