No. 199.] ^7 



allowing their sei'vice^'tb be applied more usefully in some other part 

 of the vessel. 



The stahility of materials is perhaps better obtained by the putting 

 theni together in a proper ybrm rather than in choice of the material 

 itself. In all frame work the triangle is that form, and in the trussing 

 of briilges, we see examples of it, ais in the model before us of a bridge 

 over Buffalo creek, exhibited by the New-York Draw Bridge Com- 

 pany. It is a lattice bridge, having the trainway about one fourtli 

 the distance up from the bottom: The lattice is the only kind of 

 suspension bridge which can bear the impact of a railway train, and 

 much (though not all) of its stability is due to its triangular framing: 

 the railway floor is supported on cast iron arches, and the strain on 

 the sides taken off by cross girders. 



' In the vertical gate, which is exhibited on the bridge, we have' 



another instance of the triangle producing stability: the diagonal tie of 



each gate comes to an angle below, and when the gate is closed, with 



the ctots bar laid down as the bajse of the triangle, the strength of tb.e ' 



gjatf i^'iQiiia!iedi2.tcly Lncreasc'dL ' 



t 



In thfi department of time piectt Mr. Giroud has signalized bioi.- ■ 

 self by the invention of his new detached lever escapement, which he 

 has applied to clocks and watches: it has two points of repose, allows" 

 of backward movement, and is a decided improvement to time keepers. ' 

 It has cost Mr. G. much time and great labor to perfect his invention, ' 

 he having to make much of the machinery which is necessary for form- 

 ing' the escapement with mathematical precision of outline. 



There are few countries in the world blessed by Providence with" 

 such enormous quantities of coal and iron as this. Yet from causes, 

 to which I shall bye and bye allude, the iron manufacture does not 

 play the important part it should. It is comparatively a new busi- 

 ness, being only of a fefw'years growth ; hence it is, that in the depart- 

 ment of fine cutlery, I cannot find any returns of export during last 

 year, at least not in that quantity which would constitute a national 

 item. Not only do we not export, but the import is very large ; for 

 in England three fourths of the whole manufacture is destined for the 



