JERUSALEM ARTICHOKE. 159 



is used, in others not enough. It were very desirable thai certain 

 experiments were undertaken which should fix the pre per quantity 

 of seed-potato to be used for each variety of soil and situation. 



The Jerusalem Artichoke, {Helianthus tuherosus.) This plant is 

 generally believed to be a native of South America, but M. de Hum- 

 boldt never met with it there, and according to M. Correa, it does 

 not exist in Brazil. The property which the tubers of this plant 

 have of resisting the cold of our winters, and several botanico-geo- 

 a^raphical considerations, lead M. A. Brongniart to presume that the 

 plant belongs to the more northern parts of Mexico. 



The Jerusalem artichoke rises to a height of from 9 to 10 feet; 

 it flowers late, and I have not yet seen it ripen its seeds. It is pro- 

 pagated by the tubers which it produces, and which are regarded^ 

 for good reason, as most excellent food for cattle ; in times when 

 the potato was not very extensively known, it also entered pretty 

 largdy into the food of man ; when boiled, its taste brings to mind 

 that of the artichoke, whence the name. 



The tuber of the Jerusalem artichoke, from an analysis of M. 

 Braconnot, appears to contain in 100 parts : 



Uncrystallizable sugar . . . 14.80 



Inuliue 3.00 



Gum 1.22 



Albumen 0.99 



Fatty matter 0.09 



Citrates of potash and lime . .... 1.15 

 Phosphates of potash and lime . 0.20 



Sulphate of potash . . . 0.12 



Chloride of potassium 0.08 



Malates and tartrates of potash and lime . . 0.05 



Woody fibre 1.22 



Silica 0.03 



Water 77.05 



100.00 

 M. Payen found a larger proportion of sugar in this tuber than that 

 stated above, and he ascertained that the fatty matter consists chiefly 

 of stearine and elaine. In the Jerusalem artichoke I myself found : 



Of dry matter 20.8 



Water ■- 79.2 



lOO.d 



One trial for azote would lead me to conclude that M. Braconnct 

 had estimated the albumen too low in his analysis, or, as is more 

 probable, that several azotized principles had escaped him. The 

 dried tuber gave me 0.16 of azote, a number which would indicate 

 1.0 as the proportion of vegetable albumen. There are few plants 

 more hardy and so little nice about soil as the Jerusalem artichoke ; 

 it succeeds everywhere, with the single condition that the ground be 

 not wet. The tubers are planted exactly like those of the potato, 

 and nearly at the same time ; but this is a process that is performed 

 but rarely, inasmuch as the cultivation of the helianthus is incessant, 



