240 INDEX. 



pleasantness of fruit to the taste depends on two elements iu 

 its substance : the juice, and the pulp containing it, which 

 may properly be called Nectar and Ambrosia. We have there- 

 fore in all four essential products of the Seed and Husk 



A. Farina. Flour 156 



B. Oleum. Oil 158 



C. Nectar. Fruit-juice 158 



D. Ambrosia. Fruit-substance , 158 



Besides these all-important products of the seed, others are 

 formed in the stems and leaves of plants, of which no ac- 

 count hitherto has been given in Proserpina. I delay any ex- 

 tended description of these until we have examined the struct- 

 ure of wood itself more closely ; this intricate and difficult 

 task having been remitted (p. 122) to the days of coming 

 spring ; and I am well pleased that my younger readers should 

 at first be vexed with no more names to be learned than those 

 of the vegetable productions with which they are most pleas- 

 antly acquainted : but for older ones, I think it well, before 

 closing the present volume, to indicate, with warning, some 

 of the obscurities, and probable fallacies, with which this 

 vanity of science encumbers the chemistry, no less than the 

 morphology, of plants. 



Looking back to one of the first books in which our new 

 knowledge of organic chemistry began to be displayed, thirty 

 years ago, I find that even at that period the organic elements 

 which the cuisine of the laboratory had already detected in 

 simple Indigo, were the following : 



Isatine, Chlorindine, 



Bromisatine, Chlorindoptene, 



Bibromisatine ; Chlorindatmit ; 



Chlorisatine, Chloranile, 



Bichlorisatine ; Chloranilam, and, 



Chlorisatyde, Chloranilammon. 

 Bichlorisatyde ; 



