Engineering Wonders of the World
Volume I

16 ENGINEERING WONDERS OF THE WORLD. down the Tigris towards India, the ships of Alexander the Great were hindered by a dam that had been thrown across the river. There is plenty of evidence to show that from the earliest times the inhabitants of the Nile and Euphrates valleys were well acquainted with the science of irrigation. The public engineering works carried out by the Romans are in many ways marvellous. At a very early date in its history Rome was provided with at least Roman one great cloaca, or sewer, and Sewers. others were added as the need arose. These main sewers were very solidly built of large stones weighing up- wards of 3 tons, and portions of them remain in good condition to this day. The aqueducts which supplied Rome and some of the greatest cities of her Empire with water are, even in their present ruinous condi- tion, sufficient proof that their builders were great engineers. “ The least ob- servant visitor to Rome is awed Roman and impressed by the ruins of the Aqueducts, aqueducts.....When he comes to inquire a little more closely into the history of these wonderful structures, he finds not only that the ignorance of scientific principles to which it was once the fashion to attribute their origin did not exist, not only that the popes of later days have succeeded in restor- ing a few of them so as to make them prac- tically useful in quenching the thirst of the modern Roman, but also that the aqueducts have a curious and interesting history of their own which, admirably illustrates the life and progress of the great Republic. As her for- tunes mounted, so the arches rose higher and THE WONDERFUL ROMAN AQUEDUCT AT SEGOVIA IN SPAIN. It has 109 arches, some of which are 100 feet high. The length of the arch portion is about half a mile. (1,408)