The following table is made up of data from that work. 17 The table is arranged to show, First, the name of the water or Aqueduct ; Second, the era of its construction ; Third, the length of each Aqueduct in miles and decimals ; Fourth, the cubic feet discharged in 24 hours, and Fifth, the gallons in wine measure. NAME. ERA. LENGTH. CUBIC FEET. GALLONS. B. C. 312 10,3250 3,706,575 27,724,181 2. Old Anio " 273 36,6775 8,932,338 66,813,887 3. Marcian " " 146 56,9417 9,525,390 71,249,917 4. Tepulan " 5. Julian " " 127 ) " 35 5 14,2341 ( 903,795 I 2,449,386 6,760,386 18,321,407 6. Virgin " " 22 14,3116 5,085,624 38,040,467 7. Alsietina " A. D. 14 20,4526 796,152 5,656,016 8. Claudian " " 49 42,1989 9,356,817 96,988,991 9. New Anio " " 90 54,1644 9,622,878 71,979,127 249,3058 50,378,955376,834,379 Some auxiliary supplies or feeders make the total length of the Roman Aqueducts, at that period, exceed 255 miles. The names of the Roman Aqueducts are taken from those of the River or Lake which supplies them, or from the emperors who caused them to be constructed. Fronti- nus gives the following as the origin of the name Virgin Aqueduct : " It is called the Virgin (Virgo), because it was a young girl who showed some veins to a few soldiers who were in search of spring water. Those who dug followed these veins and found a great quantity, and there is a paint- ing in a little temple erected close by the source representing this event." 18 Some of the principal Aqueducts constructed by the ancient Romans in other parts of Europe. Aqueduct of Nismes. This is probably one of the most ancient Aqueducts con- structed, out of Rome, by the Romans. It is attributed to Agrippa, son-in-law of Augustus, to whom that emperor gave the government of the country becoming a Roman Colony. Agrippa, flattered by the honors which he received from the inhabitants of Nismes, made his residence there : he en- closed the town with new walls, built baths, and probably the Aqueduct of the bridge of Gard ("pont du Gard") for bring- ing water to them. This Aqueduct is nearly thirty miles in length, forming, in its course, the figure of a horse-shoe. It brought water from the fountains of Eura and Airan, situated in the neighbor- hood of the town of Uzes. The bridge of Gard was about the middle part of the work, and the Aqueduct terminated at Nismes. This Aqueduct traversed a very mountainous country, piercing through mountains and crossing valleys by means of arches upon arches, forming magnificent structures en- tirely of cut stone. The Aqueduct or channel-way is formed of stone throughout the whole length. The bottom of the interior has a curved form, being an arc of a circle; the sides 19 are vertical, and the top covered with a flagging of cut stone, except where it is under ground, in which situation the top is covered by an arch of stone. The interior face of the walls and the bottom were covered with a coat of plastering two inches in thickness, composed of quick-lime, fine sand, and brick nearly pulverized. This coating has now a tenacity and consistence equal to the hardest stone. The size of the channel-way is the following : 4 feet wide and 5i feet high, except where the top is covered with an arch, in which case it is H feet high in the interior. The descent of the Aqueduct is 1 foot in 2500 feet, or 2^ feet per mile. The water which flowed in this Aqueduct formed a depo- sit upon the sides, of lime, until nearly half the channel was closed; this deposit amounting to a thickness of 11 inches on each side. By the height of this deposit it has been ascer- tained that the water flowed generally with a depth of 3f feet. The pont du Gard is that part of the Aqueduct of Nis- mes which crosses the deep valley in which runs the Gar- don or Gard. This part, considered alone, is one of the noblest monuments built by the Romans among the Gauls. It is composed of three ranges of arches one above another. The first range, under which the Gardon flows, is formed by 6 arches ; the second by 11, and the third by 35, all of which are semicircular ; supported upon piers of greater or less height. 20 The channel in which the water flows is upon the top of the third range of arches, and is 160 feet above the water of the river. The whole length of this bridge is about 900 feet. The bridge of Gard having been broken down at the two extremities, at