Near the old palace stood a vast structure, known from all antiquity, and celebrated in every age as the most wonderful structure ever yet built; viz., the temple of Belus. We have given some account of it from Herodotus already. A tower of vast size stood in the middle of it. At its foundation it was a square of a furlong on each side; that is, half a mile in its whole compass, and the eighth part of a mile in height. It consisted of eight towers, built one above another, gradually decreasing in size to the top. Its height exceeded that of the largest of the pyramids[106]. It was built of bricks and bitumen. The ascent to the top was on the outside, by means of stairs, winding, in a spiral line, eight times round the tower from the bottom to the top. There were many large rooms in the different stories, with arched roofs, supported by pillars. On the top was an observatory, the Babylonians having been more celebrated than any other people of ancient times for their knowledge of astronomy[107]. Notwithstanding the opinions of many, that this tower was built expressly for astronomical purposes, it appears certain that it was used as a temple also; for the riches of it were immense; consisting of statues, tables, censers, cups, and other sacred vessels, all of massy gold. Among these was a statue, weighing a thousand talents of Babylon, forty feet high. Indeed, so rich was this temple, that Diodorus does not hesitate to value all it contained at not less than six thousand three hundred Babylonian talents of gold; which implies a sum equivalent to twenty-one millions of pounds sterling! Surely some error must have crept into the MS. This temple stood till the time of Xerxes. On the return of that prince from Greece he plundered it; and then caused it to be entirely demolished. When Alexander returned from India, he formed the design of rebuilding it upon the ancient plan; and probably, had he lived, he would have accomplished his wish. Ten thousand men were put to work to clear away the rubbish; but he died in the midst of his preparation. Many of the chief erections in this city were planned and executed by Semiramis. When she had finished them, she made a progress through the various divisions of her empire; and wherever she went left monuments of her magnificence, by many noble structures, which she erected, either for the convenience or the ornament of her cities[108]. She was the best political economist of ancient times, and may truly be styled the first utilitarian: for she applied herself to the formation of causeways, the improvement of roads, the cutting through mountains, and the filling up valleys. She applied herself, also, most particularly, to the forming of aqueducts, in order that water might be conveyed to such places as wanted it: in hot climates desiderata of the first importance.