RAILWAY CONSTRUCTION. 223 



the workman's endeavour to avoid damaging the point of his 

 augur by forcing it entirely through the sleeper, and bringing it 

 in contact with a stone. Augur-holes bored wide to gauge will 

 remain out of gauge, and although the spike may be driven down 

 firm in its position, a space will be left for play between the rail- 

 flange and spike. 



Fig. 329 is a sketch of a dog-spike for flange rails which the 

 writer has used for many years both abroad and at home, and 

 which can be driven without any boring at all. The back of 

 this spike is made perfectly straight, half of the front side is 

 made parallel to the back, and the remainder is tapered down to 

 a chisel point not exceeding fa of an inch thick, the entering 

 edge on the face being narrowed down to of an inch in width. 

 Three jags or spurs are cut on each side of the tapered portion, 

 or twelve in all, and add greatly to the holding power. Not- 

 only can this spike be driven without any boring, but it possesses 

 the additional advantage that in driving it down its taper or 

 wedge-like shape causes it to drift hard up to the edge of the 

 flange of rail, an element of great value in securing the exact 

 gauge of line. With these spikes permanent-way laying can be 

 carried on very rapidly, and they are especially valuable when 

 making alterations, as augurs for spike-boring can be dispensed 

 with altogether. 



Wood screws with square heads similar to Fig. 330 are some- 

 times used for fastening flange rails to wooden sleepers. They 

 are passed through holes punched or drilled in the flanges of the 

 rails, and are intended to preserve the gauge as well as secure 

 the rails to the sleepers. Experience has shown that these wood 

 screws possess very limited holding power. The screwed portion 

 of the bolt cuts but a very imperfect and weak holding thread 

 in the soft wood of an ordinary sleeper, moisture insinuates itself 

 into the bolt-hole, rusting the bolts and decaying the surround- 

 ing timber, and in a very short time the bolts become loose and 

 incapable of holding the rail down firmly. As permanent- way 

 fastenings wood screws are very inferior to crab bolts. 



Crab bolts, as in Fig. 331, may be made either with square 

 or hexagonal heads, and with three spur-nuts or four spur-nuts, 

 as in A or B. The length of the bolts will depend upon the 

 thickness of the sleeper or timber-work through which they 

 have to be inserted. The bolt is pushed down through the hole 

 bored in the sleeper, and the crab-nut put on from underneath. 



