Ch. Vm. SOUTH AMERICA. 169 



whence it was taken. Some time after, it undergoes 

 a fecond operation ; but without yielding fo much 

 juice as at firft ; and at the third or fourth very little, 

 by which means the ñíh is exhaufíed beyond re- 

 covery. In 17^4, being in the lieutenancy of Santa )C 

 Elena, I had the fatisfadion to fee this liquor ex- 

 tra6ted according to the firft proccfs, and fome threads 

 died with it. This purple is far from being fo com- 

 mon as fome authors have imagined ; for, though the 

 fifh increafes, yet fo large a quantity is neceirary to 

 die a few ounces of thread, that little of it is feen ; 

 and indeed its great price is partly owing to its fcarcity. 

 Another circumftance worthy obfervation, and which 

 increafes or diminiihes the value, is the difference of 

 weight and colour of the cotton died with it, accord- 

 ing to the diiferent hours of the day. I could not find 

 any fatisfaitory account of this property at Punta de 

 Santa Elena, where the inhabitants, being lefs cu- 

 rious, have not carried their fpeculations lb tar as to 

 be acquainted with this remarkable lingularity ; 

 whereas at Nicoya it is fo well known, that the dealers 

 in it, both buyers and fellers, are exaé^ly acquainted 

 with the times of its increafe or decreafe, fo that one 

 of the firft preliminaries to a contrail is, to fettle the 

 time when it Ihall be weighed. From this alteration 

 of the weight of the purple thread at Nicoya it may 

 be inferred, that the fame happens at Punta de Santa 

 Elena ; the turbines at both places being exaiily of 

 the fame fpecies, and without the lead viiible dif- 

 ference in colour. Another very remarkable par- 

 ticular relating to its tin¿V, and which I have heard 

 from perfons of undoubted veracity, is, that the co- 

 lour of a thread of flax is very different from that of a 

 thread of cotton. It would therefore be proper to 

 make repeated experiments, on threads of ñlk, flax, 

 and wool. 



Some, by faying that thefifli, from whence this die 

 is extra (ft ed, breeds in a ihell, by which cither the 



flat 



