OTHER VEGETABLE FIBRES. 



5^ 



Another point of the utmofl importance to be afcertained is Whether tan 



whether tanned ropes will be prel'erved bj the tan, with which w'lljrcfervc wet 



they are impregnated, when flowed away wet; as tarred ropes 



are preferv'ji^ by the tar when fo circumflanced. It is never- 



thelefs a well-known fad, that tarred cordage, when new, is Tar does not 



weaker than white; and that the difference increafes by keep- ftrengthen cord- 



' . age ; but the 



ing. Tar can therefore only be employed to preferve cordage, contrary. 



and not to flrenglhen it; fo that if tan will add itrength, or 

 even not weaken vegetable fibres, and at the fame time pre- 

 ferve them ; of how great advantage to the nation would the 

 difcovery of a convenient pradicable procefs be. For all 

 cordage, expofed to be alternately very wet or dry, requires 

 to be impregnated with a prefervative. And, to conclude this Tar not pro- 

 long note, I beg leave to obferve, that tar is not the produce ^^^^^^ ^" "°P^^^ 

 of the warmer parts of Afia. Are we, therefore, to conclude, 

 that no material, the produce of thefe parts, can be applied 

 ibr the fame end? Let us not, entertain any fuch idea. Nature 

 is abundantly kind, and furnlfhes every country and climate 

 with what is mofl: proper for the ufe of its inhabitants. 



The annexed flatement of the experiments made on the Statement of 

 iubflances there fpecified, can only be deemed an attempt [^^^^^^'^^ "" 

 towards afcertaining their relative ftrength ; and though they 

 are the average refult of feveral trials made on the flrength of 

 each cord, plain, tanned, and tarred, yet I mult acknowledge 

 they cannot be deemed any thing more than a firft eflay, chiefly- 

 owing to the lines being in general ill laid, fome more and fome 

 fefs twilled, and by no means to be compared with thofe of 

 Europe. For in fome inftances, I found a fmall one fuflain 

 a greater weight than a much larger, made exactly of the fame 

 materials. It is therefore my intention to. repeat them on a 

 larger fcale, and, if poflTible, with better made lines; for 

 every thing depends on their being exa6lly of the fame fize and 

 degree of Iwift. 



COMPARATIVE 



