Intelligence and Miscellaneous Articles. 387 



But although the immediate cause of this accident was, the vi- 

 bration arising from the measured step of the soldiers, it is not at 

 all probable that so small a number as were present on the occasion 

 would have brought down the bridge, unless there had been errors 

 of the most glaring description committed in its construction, as 

 well as something very faulty in a part at least of the materials of 

 which it was composed. 



The principal error of construction, and the only one to which 

 we feel it necessary to call the particular attention of our readers, 

 will be tolerably well understood by a reference to the subjoined 

 engravings, and the explanation which accompanies them. The 

 following sketch represents the manner in which the links of the 

 chain are generally joined together. 



The main links of which the chains are composed (A, A) (each of 

 which consists of two round bars of iron, two inches in diameter, and 

 about five feet long, but 

 represented in the sketch __ ^^ 



as broken off near their Ij j ; p 



extremities) are joined ^ L j j j H ! j -^ 



together by means of three AH | \l ^A 



short links and two bolts, ^Q 3 ^ir 



in a manner which will 

 be much better under- 

 stood by a reference to the sketch, than by any verbal descrip- 

 tion which we could give. This is obviously a very good and strong 

 joint ; for the bolts, being held both in the middle and at each end 

 by the short links, would resist an enormous tension on the main 

 links, and could not easily give way unless they were in a manner 

 shorn asunder. This excellent mode of joining the links, however, 

 appears to have been strangely departed from, and one of a very 

 inferior description adopted, precisely where the strain was the 

 greatest, and where the greatest strength ought to have been em- 

 ployed, namely, in each of the stay-chains or land-chains by which 

 the whole weight of the bridge is supported. Those chains, as we 



soldiers marched whilst on the bridge had no slight share in causing the 

 accident. Before they reached the bridge we are told that they were 

 walking ' at ease,' but when they heard the sound of their own footsteps 

 upon it, one or two of them involuntarily began to whistle a martial tune, 

 and they all at once, as if under a command from their officer, commenced 

 a simultaneous military step. This uniform motion naturally gave great 

 agitation to the bridge, the violent effects of which would be most severely 

 felt at each end. As a familiar illustration of our meaning, we may remark, 

 that if a rope, the ends of which being fastened to opposite walls, should 

 be much agitated in the centre, its motion would be far more violent at 

 the ends than in any other part. 



" It will not be irrelevant here to state that the rifle party, when they 

 passed over the bridge in the morning, walked across it in an easy manner, 

 without using the military march ; that several waggons traversed it the 

 same morning ; and that the Royal Artillery, under the command of Major 

 Chester, whilst stationed in this town, regularly crossed it with horses, 

 guns, &c., when on their way to and from Kersall Moor." 



3 D 2 have 



