Water is not a simple element, as has been supposed, but is composed of vital air, and a particular kind of air which is called _inflammable_; the same that is used to fill balloons. It has been found by experiment, that one hundred pounds of water, are composed of eighty-five pounds of vital air, and fifteen of inflammable air. [5] Water may be decompounded by a variety of means, and its component parts separated from each other. Vegetables effect this decomposition; they absorb water, and decompose it in their glands; and taking the inflammable air for their nourishment, breathe out the vital air in a state of very great purity; this may be ascertained by a very easy experiment. This vital air is received by animals into their lungs, gives them their heat, and communicates a red colour to their blood; when animals die for want of vital air, their blood is always found black. From what I have said, it is evident, that in large and populous towns, where combustion and respiration are continually performed on a large scale, the air must be much less pure than in the country, where there are few of these causes to contaminate the atmosphere, and where vegetables are continually tending to render it more pure; and if it was not for the winds which agitate this element, and constantly occasion its change of place, the air of large towns would probably soon become unfit for respiration. Winds bring us the pure air of the country, and take away that from which the vital air has been in a great measure extracted; but still, from the immense quantity of fuel which is daily burnt, and the number of people breathing in large towns, the air very soon becomes impure. From the greater purity of the air in the country, proceeds the rosy bloom found in the rural cottage, which we in vain look for in the stately palace, or the splendid drawing room. Here then are reasons for preferring the country, which no one will dispute, and whenever it can be done, such a situation ought always to be chosen in preference to a large town: this cannot be better enforced than in the words of Dr. Armstrong.-- 'Ye, who amid the feverish world would wear 'a body free of pain, of cares a mind; 'fly the rank city, shun its turbid air; 'breathe not the chaos of eternal smoke, 'and volatile corruption, from the dead, 'the dying, sick'ning, and the living world 'exhaled, to sully heaven's transparent dome 'with dim mortality. 'While yet you breathe, away; the rural wilds 'invite; the mountains call you, and the vales; 'the woods, the streams, and each ambrosial breeze 'that fans the ever undulating sky.'