vacuum, and demonstrated that the rising of water in the chamber of the pump, was produced by atmospheric pressure. As human beings were aggregated into larger societies, and the progress of civilization and refinement produced new and artificial wants, all the known modes of obtaining water from wells, springs, fountains and rivers, were found insufficient, and it became an object to devise some more compendious as well as abundant system of supply, and hence the resort to aqueducts.

As nearly all the ancient aqueducts, of which there are still any remains, are of Roman construction, it has been generally believed that works of this description were entirely unknown to other people. This, however, is an error. Among the Greeks, some are mentioned by Pausanias and others. But no particular description of these structures has reached us, and we are therefore left to conjecture. As the use of the arch was. according to the received opinion, unknown to the Greeks, as well as the law of hydrostatics, that water will rise to its own level, it seems difficult to understand how they could pass water over valleys or streams and the inference seems reasonable, ;

that their aqueducts, such as those built by Pisistratus, at Athens, that at Megara, and the celebrated one of Polycrates, at Samos, mentioned by Herodotus, were rather conduits than ranges of buildings like the Roman aqueducts.

But, at a period antecedent probably to the construction of these Grecian aqueducts, King Solomon, one thousand years before the Christian Era, appears by the accounts of modern travellers, to have constructed a similar work. In the Universal History, vol. II, p. 441, we find the following statement :