RAILROADS. 501 



the Pennine range, that runs southward from the Roman wall to the 

 Trent. The cost of canal cutting on the Leeds and Liverpool canal 

 was more than quintupled between Wigan and Bingley ; and on the 

 Rochdale and Huddersfield canals the cost of tunnelling and deep 

 cutting through the solid I'ock averaged as much as ten times that of 

 the same length on a tolerably level surface and through favourable 

 strata. The same results may be predicted with respect to the deep 

 cuttings and tunnels on the Leeds and Manchester railroad. Tod- 

 morden tunnel is seven furlongs and a half in length, having a height 

 of twenty. six feet ; and we venture to say, from a knowledge of the 

 expense of many different canal tunnels, that the cost of cutting this 

 tunnel alone, exclusively of brickwork, will not be less than £1200 per 

 fathom, makingfor the whole of that excavation an outlay of little less, 

 if at all, than a million. This estimate is not given to frighten our 

 readers, or to injure the interests of the railroad company in question, 

 but rather to furnish an illustration of one out of the many elements that 

 enter into the estimated expense of a railroad. Another matter of con- 

 sideration is the nature of the strata with reference to their firmness 

 , and solidity, a quality indispensable for the bedding of a railroad, and 

 which must be obtained by artificial means wherever the natural soil 

 is unfavourable, as, for instance at the Chat-moss, on the boggy sur- 

 face of which very many thousand loads of soil were thrown, at an 

 enormous expense, before a sufficiently firm bed could be found on 

 which to carry over the railway. It is on this quality that it depends, 

 whether in the case of cuttings and embankments brickwork or ma- 

 sonry is to be employed for supporting the sides : the cost of such cut- 

 tings must vary in proportion. As in case of a canal a porous and 

 leaky soil may be inadvertently chosen in place of one better adapted 

 for such purposes at no great distance (an instance of which occurs in 

 the Thames and Severn canal), so, in forming a line of railroad, the 

 engineer or surveyor may, owing to an insufficient knowledge of lo- 

 cal geology, fix on a country requiring artificial improvement, where 

 a tract exactly suited by nature might be found at a short distance to 

 the right or left of the surveyed line. One other consideration in es- 

 timating the expense of construction is whether stone adapted for 

 building purposes lies in the immediate neighbourhood of the pro- 

 posed road. The diminution of expense in building materials may 

 often more than counterbalance physical disadvantages. 



We next jiroceed to notice those particulars in the construction 

 of railroads, which depend in a great measure on the management 

 and skill of the engineer ; and we may here observe, that it is in the 

 ingenuity with which a level or nearly level surface is maintained at 

 the least possible sacrifice of labour that the talent of the engineer 

 chiefly consists. A knowledge of the degree of slope in the differ- 

 ent parts of a railroad is of the highest importance ; as without this 

 it would be impossible to estimate either the original outlay or the 

 permanent cost of transport. It may, besides, be worth while to make 

 a sacrifice in the first outlay to attain an economy in the transport: 

 and this must be well considered, for a want of due attention to 

 it may irreparal)ly injure the permanent interests of the railroad 

 speculators. Wc think it indeed desirable that the shareholders 



