vl PREFACE. 



different works of construction, as these must always vary to a 

 very large extent, according to the locality, facility of supply, 

 and current prices of materials. 



Every railway scheme which is the outcome of public enter- 

 prise has its commercial aspect and influence. The large sums 

 to be invested in its construction are expected to yield perma- 

 nent and increasing returns, and this desirable end can only be 

 attained where there is thorough efficiency in works and equip- 

 ment, and a full compliance with those national regulations 

 which control matters connected with public safety. The correct 

 dealing with the technical requirements and structural features 

 of the undertaking must always precede all other considerations, 

 as the constituted authorities will exact a proper fulfilment of all 

 the statutory obligations, regardless of the prospective remunera- 

 tion to the promoters. A stroke of the pen may change a train- 

 service, or alter the rates and tariffs, but a modification in the 

 works of construction arising out of errors or oversight, would 

 entail a heavy expenditure and tedious delay. The essential 

 point of every railway undertaking must be its suitability and 

 completeness in every respect for the duty for which it is 

 intended. 



Notes of what has been done are always valuable for con- 

 sideration and comparison, and that the following brief de- 

 scription and sketches may be found useful for reference, is 

 the earnest wish of the writer. 



W. H. MILLS, 



M.lNST.C.E. 



