20 NUTRlTtON OF VEGETABLES. 



* . analysed, were found to contain 6*7 of pure potash ; 7-35 of 



sulphate of potash; a small quantity of phosphate of lime ; 

 and the rest was carbonic acid. 



Residuum con- Thg residuum left after lixiviatine: the ashes appeared to 

 tained sulphur. . ,, , ..., ... 



contam sulphur, as on pounng nitric acid over it sulphuret- 

 ted hidrogen was given out ; but I could not find any phos- 

 phoric acid in it. I did not examine it for the earths, as 

 these might have been said to have been taken up from the 

 sand. 

 Compared with Having thus examined these plants, I thought it might 

 from •r'irdeii ^^^ ^^ amiss to compare their produce with that of some 

 irioui'd. others, which had grown in common garden mould. Of 



these dried 372 gr. afforded but 34 of ashes, which it is true 

 were very saline, and yielded l6 gr. of saline matter, con- 

 sisting of carbonate and sulphate of potash. In the incinera- 

 tion of these plants too I observed a very copious production 

 of ammonia, on pouring a little water on their ashes while 

 gtill hot. 

 Whence these -^"^ whence come these earths, alkalis, acids, metals, snl- 

 substancts phur, phosphorus, found in plants, that have had no ali- 

 nomished only ^""^"^^ ^^'^ P^''^ water? Can vitality, 'in conjunction with 

 with water? light and heat, determine certain quantities of oxigen and 

 Are they all hidrogen to form by peculiar condensations those substances 



formed ftorn w]^j(.}j j^^ve been considered as simple? this mlaht put us on 

 oxigen and hi- . . i i i 



drogen? examkiing in a new point of view all those substances, that 



chemistry has not yet been able to decompose, and thus per- 

 haps the conjectures, that have been advanced by some, may 

 be verified, 

 U\t the same We may even extend these remarks to animallzation, sup- 

 withaoimals? ported by the well-known experiment of Rondeletius, who 



saturated with nitric acid I have not ascertained. I must observe, how- 

 ever, that 1 have found no nitric acid in wormwood, 100 parts of the ashes 

 of which afford nearly 75 of saline matter, according to Wiegleb. This 

 The alkali large quantity of alkali has appeared to me to be partly saturated with a 

 partly saturat- peculiar inaiter, which is deposited by a decoction of the fresh plant, 

 cd with a pe- and may be precipitated abundantly by nitrate of lead. This matter dis- 

 cuhar matter: solves very well in alkalies neutralizi)ig part of their properties : it is the 

 same that Mr. Vauquelin has found in some species of cinchona. Does 

 is-itcin hon'n ' ^xist in all b.tier plants? and is it this which in chichona and worm- 

 wood cures iritermittent and low fevers ? 



kept 



