History of Sanitation

14 HISTORY OF SANITATION was possible to hear the voice of one man calling to another across the rock separating them, and the last day of the piercing, the miner’s pick met against pick. The height of rock above the heads of the miners was 100 ells. Then Aqueduct near Tunis, leading to Ancient Carthage the water flowed into the reservoir over a length of 1,200 ells.” This tunnel was cut through a mountain of solid rock. The tunnel varied in dimensions from /s of a yard to a yard in width, and from 1 to 3 yards in height, accord- ing to the hardness of the rock. The magnitude of this undertaking can be realized only when it is considered that the tunnel was constructed without the aid of blasting agents, machine drills, steam, electricity or any of the great forces or devices now con- trolled by man and used in modern engineering construc- tion. At a later period in the world’s history, Roman engi- neers, tunneling through the rock, used fire as well as chisels to disintegrate the rock. The usual method of pro- cedure was to build an intensely hot fire against the rock, and when the rock had been heated to the right tempera- ture it was drenched with cold water to crack and disinte- grate it. According to Pliny, vinegar was sometimes used instead of water, under the impression that it was more effective in disintegrating rock.