- 114 Plan of the Receiving Reservoir, - - - - - 116 Isometrical View of the Distributing Reservoir, - - - 119 9. " The radiant aqueducts Turn their innumerable arches o'er The spacious desert, brightening in the sun, Proud and more proud in the august approach : High oe'r irriguous vales, and woods, and towns, Glide the soft whispering waters in the wind, And here united pour their silver streams, Among the figured rocks, in murmuring Falls, Musical ever." The Ruins of Rome. INTRODUCTORY CHAPTER. A supply of pure and wholesome water is an object so essential to the health and prosperity of a city, that it should form one of the leading features of the public improvements which characterize its growth. The advantages arising from it are so numerous, and the comforts so great, that every effort should be made to accomplish it. The means which have been resorted to for such purposes in almost every city of importance in the Old World, are examples for us of the New, and should induce us early to avail ourselves of that important element of health. We contemplate with mingled emotions of wonder and admira- tion, those works of art which were achieved by ancient Rome in her palmy days of wealth and power, and among them we find that her Aqueducts hold a prominent place. Among the ruins of cities whose history is shrouded in mystery on this continent, we find provisions for bringing water from distant sources. In the wilds of Central America, 3 10 the persevering traveller finds ruined cities buried in the depths of the forest, where nature is at work covering and concealing them : among those ruins he tells us of the Aque- duct. We find them also among the ruins of cities along the western coast of South America. With such examples be- fore us, we may consider that by the construction of the Croton Aqueduct for supplying the City of New- York with water has been secured an important measure for the pro- motion of its growth. Many cities of the United States have directed their atten- tion to this object, and some have been fortunate in finding a supply of water near at hand, but others will look towards distant sources for a supply, and will, ere long, resort to the construction of Aqueducts. In the history of cities built in remote periods of antiquity, we find mention made of plans for supplying water, and among remains of those cities which are found at this day, are traces of Aqueducts. We have accounts of Aqueducts constructed under the reign of Solomon, and the remains of them still existing in Palestine, give evidence of an ex- tensive acquaintance with the principles of hydraulics among the Hebrew architects. The Pools of Solomon, which are mentioned by travellers who combine in their researches a regard for the arts as well as the religion of Judea, are connected with a scheme for supplying Jerusalem with water. The vast expense incurred in the construction of Aque- 11 ducts by the Ancient Romans, as well in Italy as in other countries of Europe, proves the value that was attached by that people to a plentiful supply of pure water, and the de- tails of the plan of construction of the different works, evince an acquaintance with the principles of hydraulics which, at this day, is not generally accorded to them. That they understood the principle that water seeks the level of its source after encountering depressions in its conduit, is suffi- ciently proved by instances, in works constructed by them, where the inverted syphon of pipes was used in crossing valleys. That this plan was not generally adopted by them in cases where great expense has been incurred to maintain the uniform declivity of the conduit over valleys, may be ac- counted for perhaps by the want of proper material for the construction of pipes. In cases where this plan has been adopted leaden pipes were used, and since it is only within the last century that iron pipes have been invented, we may reasonably conclude that considerations of such a nature would have induced them to adopt the more expensive plan of maintaining the general inclination of the conduit by vast structures of masonry. By substituting inverted syphons instead of maintaining a uniform declivity in the conduit, would not give the requisite discharge of water at the elevation of the terminus of the Aqueduct, and perhaps they preferred, rather than diminish this elevation of the supply of water, to incur the expense of high structures across valleys. The Roman Emperors, with all their power and the wealth which was at their command, knew how to perpetuate the glory of their reign by the erec- 12