A manual of the principles and practice of road-making: comprising the location, construction, and improvement of roads, (common, macadam, paved, plank, etc.) and rail-roads. By W. M. Gillespie ...

CONTENTS. 11
PAGE
6. ROADS OF OTHER MATERIALS........................ 255
Bricks........................................................... ib.
Concrete........................................................ ib.
Cast iron...................................................... ib.
A sphaltum...................................................... 256
Caoutchouc...................................................... ib.. ROADS WITH TRACKWAYS.......................... 257
Of stone................................... v.... -..*.... ib.
Of wood........................................................ 259
Of iron...................................... 260
CHAPTER V. RAIL-ROADS.....................................261
I. WHAT RAIL-ROADS OUGHT TO BE...........................264
1. AS TO THEIR DIRECTION.................................. 270
Economy of straightness...................................... ib.
Evils of curves................................. 271
2. AS TO THEIR GRADES............................... 276
Loss of power on ascens.................... ib.
Compensating power of descents.......................... 280
3. AS TO THEIR CROSS-SECTION........................ 282
The broad and narrow gauge question................... ib.
Advantages of the broad gauge........................ 283
Objections to it........................... 284
The break of gauge....................... 285
Width of road-bed............................................ 288
II. THE LOCATION OF RAIL-ROADS-.....................290
III THE CONSTRUCTION OF RAIL-ROADS................ 291
1. FORMING THE ROAD.BED............................. i.
Excavations.................................................... i5,
Tunnels......................................................... 293
Embankments.................................................. 294
Ballasting............................................ 296