VI CONTENTS 



CHAPTER PAO 



V XVI. SPECIAL TREACHEROUS GROUND METHOD; ITALIAN METHOD; 



QUICKSAND TUNNELING ; PILOT METHOD 167 



XVII. OPEN- CUT TUNNELING METHODS; TUNNELS UNDER CITT 



STREETS ; BOSTON SUBWAY AND NEW YORK RAPID TRANSIT, 180 

 XVIII. SUBMARINE TUNNELING; GENERAL DISCUSSION; THE SEVERN 



TUNNEL 201 



v XIX. SUBMARINE TUNNELING (continued) ; THE EAST RIVER GAS 



TUNNEL ; THE VAN BUREN STREET TUNNEL, CHICAGO . . 208 

 XX. SUBMARINE TUNNELING (continued) ; THE MILWAUKEE WATER- 

 WORKS TUNNEL 230 



XXI. SUBMARINE TUNNELING (continued) ; THE SHIELD SYSTEM . . 242 

 XXII. ACCIDENTS AND REPAIRS IN TUNNELS DURING AND AFTER CON- 

 STRUCTION 266 



XXIII. RELINING TIMBER-LINED TUNNELS WITH MASONRY .... 280 



XXIV. THE VENTILATION AND LIGHTING OF TUNNELS DURING CON- 



STRUCTION 290 



XXV. THE COST OF TUNNEL EXCAVATION, AND THE TIME REQUIRED 



FOR THE WORK 300 



INDEX. 309 



