72 CORRESPONDENCE OF RAY. 



this rule is far from being general, as tliey confess, as 

 • also you may observe in reading Mr. Boyl. 



As for what concerns their experiments about pismires, 

 they give you leave to dispose of them as you think 

 good, and do not refuse to own them. They have dis- 

 tilled beetles, and many sorts of erucas, but not bees, or 

 any of that kind ; as also fish and flesh. They desire 

 that somebody would endeavour to rectify this spurit as 

 highly as it is capable, by impregnating calcined viride 

 csris with it several times, or some such like fixed salt, 

 which may retain the spirit until the phlegm be raised by 

 a gentle heat ; for, unless there be some such retinaculum, 

 the spirit and phlegm Avill rise together. If it be thus pre- 

 pared, they think it will prove a very strong dissolvent. 

 They think the best way of getting this spuit pure is by 

 putting the insects into water, for so you have nothing 

 but the acid juice : if you distil the animals themselves, 

 there may perhaps something arise from the other parts 

 of their bodies of an heterogeneous nature ; but the best 

 of all will be to try both ways, and observe the diflference, 

 if there be any. 



As to what concerns the preservation of juices, they 

 do not tie themselves strictly to spirit of sulphm-, although 

 they use it more than any other. Other acid spirits vrili 

 do the same, and sometimes better for some particular 

 herbs ; and therefore they use them indifferently, accord- 

 ing as they find, upon trial, any convenience or prejudice ; 

 and sometimes they perfume their vessels with smoke of 

 sulphur, and sometimes not. 



Note. — Although some of these observations and ex- 

 periments of the two Fishers of Sheffield, and those that 

 follow of Dr. Hulse's, are in the Philosophical Transac- 

 tions, yet these letters, containing some other considerable 

 observations beside these, I thought it convenient to pre- 

 sent the reader with the letters as I found them, without 

 mangling of them. W. D[erham]. 



