74 RAILWAY CONSTRUCTION. 



whether of iron or timber, must be stronger than the inter- 

 mediate posts, firmly fixed into the ground, and well stayed, 

 to withstand the pulling and tightening of the wires. There 

 are many places where a quick fence would not grow, and where 

 the ground is too soft to carry a wall In such cases a good 

 galvanized- wire fencing will fulfil all requirements. The strand 

 wire is better than the plain wire, as its method of manufacture 

 necessitates the use of a superior material, and it is easier to 

 straighten and keep in good order. An extra strong fence is 

 often made of six, eight, or more rows of round rod-iron secured 

 to wrought-iron uprights of bar-iron or tee-iron. 



In hot countries abroad an excellent fence is obtained by 

 planting a species of cactus or aloe in a similar manner to the 

 quick fences at home, and as shown in Fig. 66. These cactus 

 plants are readily obtained, are very hardy and quick in growth, 

 and with their large spike-shaped leaves form such an almost 

 impenetrable barrier that few animals will attempt to pass. 



Road approaches to bridges over or under the line, or to 

 public road level crossings, may be fenced in the same manner 

 as the line proper. If quicks are adopted, it will be necessary 

 to put up a light wooden fence also to protect the young plants 

 until they are well grown. Near towns and villages it is 

 frequently found advisable to adopt a specially strong wooden 

 fence, or close-boarded fence, where the approach is an embank- 

 ment, and too newly made to carry a wall. 



Gates for farm or occupation level crossings may be made of 

 wood or iron. As a rule, iron gates are preferred, as they can be 

 supplied at the same cost as wood, and are very much more 

 durable. Gates for public road level crossings have to be so 

 placed that they will either close across the railway or across 

 the road ; their length will therefore depend upon the width and 

 angle of the road crossing. It is better to make these gates of 

 wood, so that, in the event of a train running through them, 

 there may be less risk of injury to life and rolling-stock than if 

 they were made of iron. For footpath crossings, small gates, 

 wickets, or stiles may be adopted of such form as may be found 

 most suitable for the requirements. 



Culverts and Drains. Before proceeding with the formation of 

 the embankments, it is necessary to construct the culverts and 

 drains which will be covered over by the earthworks. . Any 

 existing drains which may be of too light a description must be 



