every kind in the vicinity.* All work of repair, was however, as much as possible suspended in the summer season, as then the free use of the water was most needed and agreeable.t The spring and autumn were the working periods. Moreover, a moderate temperature was deemed advantageous, as permitting the masonry to be laid with the degree of humidity deemed essential to its perfection and ultimate solidity, excessive heat and cold being alike unfavorable

to such a result. Above all, it was a rule, before beginning any reparation, to provide on the spot, every thing that could be required, and in sufficient quantity to ensure a rapid execution.

Whenever any of the Arcades within seven miles of the city, and by means of which several streams were at once conveyed, were undergoing repair, the stream was continued unbroken through leaden pipes, across that portion of the mason work.J To preserve these noble structures from dilapidation, Agrippa, who was the first national superintendent, formed a class of slaves, who were solely employed on the repairs.

* Front, p. 203. Stuart, art. Aqueducts. t Ibid. I Front, 204,

24 PRELIMINARY ESSAY.

These at first numbered 250 but at his death he bequeathed them to Augustus, who transferred them to the public. Claudius established another company of fountaineers, to about 460 persons, divided into differduring the erection of his aqueduct, amounting ent classes, and with distinct duties. There were the comptrollers, the keepers of the

castellum, inspectors, paviours, stuccoers, and other workmen. A portion of these were execute with promptness such repairs, as, without being exlodged in the city, in order to tensive, demanded immediate attention. Others were stationed near the reservoirs or