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nished more than is consistent with the temperature ofany given body, will have a tendency to destroy its equi-librium ; the earthy elements by repletion, the aerial bythe weight of the atmosphere. If any one doubt this, lethim study the different natures of birds, fishes, and ani-mals of the land, and he will easily perceive the truth ofthese principles, from the variety existing among them.For there is one flesh of birds, another of fishes, and an-other, very different, of land animals. Birds have a smallproportion of earth and water in their nature, a moderatequantity of heat, and a considerable portion of air; whence,being light by nature, from their component elements,they more easily raise themselves in the air. Fishes, bynature adapted to the watery element, are compoundedof but a moderate degree of heat, a considerable pro-portion of air and earth, and a very small portion ofwater, the element in which they live; and hence, easierexist in it. Wherefore, when removed from it, they soondie. Terrestrial animals, being constituted with muchair, heat, and water, and but little earth, cannot live in thewater, on account of the quantity of that element naturallypreponderating in their composition. Since, then, we arethus constantly reminded, by our senses, that the bodiesof animals are so constituted, and we have mentionedthat they suffer and die from the want or superabundanceof any one element not suitable to their temperament,surely much circumspection should be used in the choiceof a temperate and healthy site for a city. The preceptsof the ancients, in this respect, should be ever observed.They always, after sacrifice, carefully inspected the liversof those animals fed on that spot whereon the city wasto be built, or whereon a stative encampment was in-