In an edifice constructed on the plan of the Egyptian Temple, where pillar stands crowded behind pillar, in range beyond range, to give support to the ponderous architrave and marble roof, the overturning of two of these columns would produce but a very partial disintegration. The very circumstance, also, of there being no remains in a country where once stood the most renowned cities, proves the perishable nature of the substance chiefly employed. There is evidence, also, that stone and wood were often, perhaps usually, combined--the first as a columnar or pier-like support, for horizontal beams of the latter. This plainly appears to have been the case in the oldest ruin existing in this part of the world, namely, Persepolis, where the marble columns evidently bear marks of having been connected by cross beams of wood, and to have supported a roof of the same light structure. Hence the easy conflagration of this abode of the Persian kings, in a debauch of Alexander. The columns are loftier, further apart, and fewer in number, than in Egypt. Had not the illustration of the general subject been of more importance in the establishment of this point, reference might at once have been made to the early temples of Greece, which, even to the age of Xerxes, were structures of wood; and to the well-known difference of style between them and those of Egypt. Thus we have the second species of architectural design; and again find the facts, recounted by history, according with deductions from _a priori_ consideration of the nature, objects, and origin, of the art itself. It may afford illustration of the certainty with which the principles of reasoning operate, while the fact is singular, that ancient writers describe the huts of the nomadic tribes on their dispersion, or, at least, the earliest recorded residences of mankind, as composed of poles, formed of the branches of trees, fixed in the earth, enclosing a circular space, and meeting at top, the sloping sides being covered with leaves, reeds, or skins. This is exactly the wigwam of the aboriginal inhabitant of America. So much is man the creature of the same instincts, under similar circumstances.