64 Chemical Examination of the Pollen 



which communicated its peculiar smell to the whole mass f 

 we could distinguish, however, through this mbuldy sme'll 

 that of new cheese, or the disagreeable kind of atcid which 

 we meet with in dairies. 



When we proceeded to take the matter out of the bottle^ 

 we founil that it had formed a homogeneous mass, tenacious 

 and gluey. It had a very pungent taste, like that of old 

 cheese, but by no means acid, as it was before undergoing 

 fermentation. 



It had not contracted any fetid or ammoniacal smell, as 

 happens with animal matters in putrefaction 5 we shall soon 

 see that this difference may be easily eJcplained. Its colouf 

 was a whitish gray ; but when we diluted it in a solution 

 of caustic alkali, it immediately assumed a very fine yellow 

 colour, and exhaled a sharp ammoniacal smell. 



It is evident that a good deal of ammonia was formed du- 

 ring the putrefaction undergone by the pollen, and that 

 this ammonia proceeds from the peculiar combination of 

 azot with hydrogen, both contained in the fecundating 

 dust. But how does it happen that the matter thus altered 

 exhales no fetid smell, and does not give out an ammonia- 

 cal odour ? The cause of these phoeaomena exists in the pre- 

 sence of the malic acid in the pollen of the palm tree. This 

 acid is combined with ammonia, at least partly so, in pro- 

 portion as it is formed ; while the other part of the ammonia 

 which the malic acid cannot saturate is united to the oily 

 matter, the formation of which is the necessary consequence 

 of that of ammonia. Thus there result from this putrid de- 

 composition, malato of ammonia, and a kind of am- 

 moniacal soap. Nevertheless the vegetable matter was not 

 entirely transformed into soap, for it was not totally dis- 

 solved in water ; but the portion which was dissolved, formed 

 instantly with nitric acid a coagulation like that which 

 takes place with a weak aqueous solution of soap. 



§ XI. General Result of the preceding Analysis, and Con- 

 clusion upon the Nature of the Pollen of the Date Tree. 



The experiments which have been described, prove very 



evidentl 



