38 onhf.mpand' 



Cordage manu- Hindoo ropfi-mak^r could make them ; but, in fpite of my uf- 



' moft care, they were always too hard twilled to be of the 



greateft pofllble ftrenglh *. Of each fort there were fix, when 



there was a fufficient quantity of the fibre?. Three of thera 



were about the tize of a log-line, and three a fize larger than 



and trie4 m ths a whip-cord ; one of each fizc and fort was kept white : the 



tanned and *^° average number of pounds which broke them, (for repeated 



tarred. trials were made, and always with lengths of ex ad ly four 



feet), will be found in the firft and fecond columns (5n the 



right. One of each was tanned + with the aftringent fruit 



called gaiih by the Bengalefe, (Embryopteres Glutinifera, 



Koxb. Coromandel Plants, Vol. I. No. 70,) Their ftrenglh 



is reprefented in the liiird and fourth columns of the following 



tpble. And, la(ily, one of each fort was tarred: their re- 



fpedive ftrengths will be found in the fifth and fixth columns. 



Tanning \\7e know the tanning principle ftrengthens the fibres of 



ftrengthcns ani- , , , . , ^, . , r i t • 



^al libres but leather, (animal fibres ) but are not io clear that its operation 



querc vegetable ? on vegetable matter is uniformly the fame. The attention be- 



flowed to afcertain this point in thefe experiments will, at leaft 



throw fome light on thefubjecl; and may induce others, betfer 



qualified, to extend the inquiry (here in India), where tanning 



materials abound, 



* The experiments of Reaumur, Sir Charles Knowles, and Du 

 JHamel, unirorrnly pruve, that when htmp-rope is twil^td to the 

 ufual haidnefs, which is that which brings them to two-thirds of 

 the length of their refpc61ive yarns, their flrength is leffened by 

 nearly one-fourth^ when compaied with ropes confilling of the fame 

 number of the fame yarns twifted up to only three-fourths of their 

 length. There will be no difficulty in accounting fur this differ- 

 ence, if we confider that a iktin of fibres may he twiftcd fo very 

 haul, as to break with any atttmpt to twilt it harder. In this ftate 

 the fibres are alrerdy ihained to the utmofl, and cannot fnpport any 

 weight or additional ftrain, 



t The idea of tanning cordage is far from being new ; for the 

 fifhtrmen of Afia, a?! well as of Europe, not only tan their nets and 

 lines, but r.lfo theii' fails, to give them additional flrength and du- 

 rability. The fame procefs might be produ6live of the fame effe6\s, 

 if employed o-n cordage mnde of the materials (No. 2, 5, Cj 7, 8, 

 .and 15), fpecified in thefe experiments, which induced me to re- 

 commend its being tried with fun cordage, in my letter to the 

 ]Po3rd of Trade, in Auguft, 17?7, 



Another 



