INTRODUCTION XI 



since the work was usually performed by slaves and prisoners 

 of war, who perished by thousands. To be sentenced to labor 

 on Roman tunnel works was thus one of the severest penalties 

 to which a slave or prisoner could be condemned. They were 

 places of suffering and death as are to-dsiy the Spanish mercury 

 mines. 



Besides their use of fire as an excavating agent, the Romans 

 possessed a very perfect knowledge of the use of vertical shafts 

 in order to prosecute the excavation at several different points 

 simultaneously. Pliny is authority* for the statement that in 

 the excavation of the tunnel for the drainage of Lake Fncino 

 forty shafts and a numl>er of inclined galleries were sunk along 

 its length of 3^ miles, some of the shafts being 400 ft. in 

 depth. The spoil was hoisted out of these shafts in copper 

 pails of about ten gallons' capacity by windlasses. 



The Roman tunnels were designed for public utility. Among 

 those which are most notable in this respect, as well as for 

 being fine examples of tunnel work, may be mentioned the nu- 

 merous conduits driven through the calcareous rock between 

 Subiaco and Tivoli to carry to Rome the pure water from the 

 mountains above Subiaco. This work was done under the 

 Consul Marcius. The longest of the Roman tunnels is the one 

 built to diain Lake Fucino, as mentioned above. This tunnel 

 was designed to have a section of 6 ft. x 1 ft. ; but its actual 

 dimensions are not uniform. It was driven through calcareous 

 rock, and it is stated that 30,000 men vere employed for eleven 

 years in its construction. The tunnels which have been men 

 tinned, being designed for conduits, were of small section : but 

 the Romans also built tunnels of larger sections at numerous 

 points along their magnificent roads. One of the most notable 

 of these is that which gives the road lietween Naples and Poz- 

 zuoli passage through the Posilipo hills. It is excavated 

 through volcanic tufa, and is about. 3000 ft. long and -."> ft. 

 wide, with a section of the form of a pointed arch. In order 



"Tunneling," Knrly. Brit.. 1889, ml. xxiii.. p. 633. 



