32 THE POPULAR SCIENCE MONTHLY. 



Frontinus. The number of open reservoirs was afterward increased. 

 Heavy penalties were inflicted for dipping a dirty vessel into one of 

 these reservoirs. Of the total supply, a little over one-third was 

 given to the public, and the remainder divided pretty evenly between 

 private and imperial purposes. The wealthy had water brought into 

 reservoirs within the courts of their residences, whence it was raised 

 to the upper stories in buckets worked by windlasses. This method 

 of supplying the upper stories is in use at the present time. The Ro- 

 mans had no pumps. Why the water was not conveyed upward in 

 pipes does not appear, except that in regard to the more elevated 

 parts of the city it was probably not brought in at a high enough 

 level. They possessed lead pipes of diflferent sizes, and stopcocks of 

 bronze and silver, for these have been found in various places; and 

 that they were perfectly familiar with the principle of liydraulics, 

 that water may be returned to its original level, is proved not only 

 by the construction of the filtering-places already described, but also 

 by the fact that they actually applied the principle on a stupendous 

 scale. Besides, there is a work of Vitruvius extant which recognizes 

 and gives directions for conveying water on this principle. An aque- 

 duct constructed by the Emperor Claudius, for the ancient city of 

 Lugdunum (now Lyons), possessed two inverted siphons, by which 

 the water was carried across deep valleys. There is no doubt that 

 they were acquainted, too, with the poisonous action of lead on water; 

 but, if that deterred them from raising the water, it shows they were 

 more careful in guarding against unhealthful influences than we mod- 

 erns are, for lead pipes are in general use to distribute water through 

 our houses to-day. 



The aqueducts were placed under the care of a curator aqiiarum^ 

 and afterward, in the time of Diocletian, under several magistrates, 

 called consulares aquarum. The actual attendants numbered 700, and 

 were divided into the familia publica and the familia Ccesaris. The 

 former, 240 in number, were paid by the state; the latter, 460, by the 

 emperor. With regard to the cost of building the aqueducts, it seems 

 to have been defrayed, in the majority of cases, out of government 

 funds ; but it is recorded in an inscription on the Porta Maggiore, a 

 gate of the city over which the conduits of the Claudia and Anio 

 Nevus were carried, that those two aqueducts were built by the Em- 

 peror Claudius at his own expense. Tliis gate affords a clew to the 

 reason why arcades instead of solid walls were used to cany the aque- 

 ducts across the plains : it was not solely for economy's sake, nor for 

 beauty's ; but while those considerations, no doubt, w^ere entertained, 

 the main object was, to avoid interference with the freedom of travel. 



The aqueducts were all destroyed in the Gothic wars under Vitiges 

 and Totila, but the most important of them Avere restored either by 

 Belisarius or Narses. These, however, fell gradually into decay, and 

 ultimately became useless. Pope Paul III. (1540) restored to use the 



