614 TRANSACTIONS OF THE 



going on to supplant the vegetable by the use of the mineral, 

 and nowhere will this be found more general than in the applica- 

 tion of iron in our times to almost all conceivable purposes. It 

 is not alone left for railroads, and steamships, and telegraphs, 

 and naval armaments, to consume this valuable product, but in 

 these parts, at least, we draw largely from it for our dwellings, 

 warehouses, public buildings, railroad stations, &c., and each year 

 as we advance in our experience, the demand becomes greater, 

 until we are most ready to accept the proposition of the great 

 English writer and political economist, that the civilization of a 

 community is in direct ratio to its consumption of iron. 



I leave these general ideas, however, to dwell more particularly, 

 though briefly, on iron a^ manufactured into rope, and purpose 

 showing some of its advantages in this application. 



RIGGING. 



As shipping generally furnishes the greatest market for the 

 consumption of rope, I will endeavor to compare the wire rope 

 with the hempen rope, and show some points wherein I conceive 

 lies its superiority for this purpose. You will please note I shall 

 refer entirely in this paper to standing and not running rigging. 



One advantage, then, I will proceed to say is, that wire ropes 

 of equal strength with hempen ropes, are but one-fourth part as 

 bulky, from which I argue that the sailing qualities of the vessel 

 must be improved just in the proportion that the surface exposed 

 against the wind is decreased. For example, the main stay on a 

 steamer of three thousand tons, if made of hemp rope would re- 

 quire to be twelve and one-half inches circumference, whereas, 

 if made' of wire rope of same strength, it would be decreased to 

 only five inches circumference. This advantage would be appre- 

 ciated on a vessel having auxiliary steam power when making 

 way against the wind. Another advantageous feature, and are of 

 still more importance, is the great economy in weight, being about 

 fifty per cent less. The standing rigging of a steam vessel of the 

 same size as before, three thousand tons, from her shrouds and 

 stays on her lower masts, including those of top masts, top-gallant 

 masts, royal masts, and gib gear, would weigh if made of hempen 

 rope 12.74 tons, of 2000 lbs each, while if make of wire rope, and 

 same strength, the weight would be reduced to 8.24 tons, leaving 

 a saving in favor of the wire rope of about 4.5 tons, and in a 

 sailing ship of thirteen hundred tons, the saving in weight would 

 be about the same. 



This large saving in weight, when it is remembered that the 



