38 THE USES OF PLANTS. 



3. PULSE. 



Of these leguminous plants, the seeds of which are 

 rich in the nitrogenous substance known as 'legumin' 

 and are known generally as pulse, the most im- 

 portant are Peas (Pisum sativum, Z-.), Beans (Faba 

 vulgaris, Mcench), Haricots (Phaseolus vulgaris, L.), 

 French Beans (P. multiflorus, Willd.), and Lentils 

 (Lens esculenta, Mcench). 



PEAS (Pisum sativum, L.), a cultivated form of 

 prehistoric origin, probably derived from a plant 

 native to the shores of the Black Sea, are largely 

 eaten, both in an unripe state, as a green vegetable, 

 and when ripe, as dried and split peas and pea-flour. 

 Peas are rich in the albuminoid casein, containing 

 22 per cent, of this substance. ' For i part of flesh- 

 formers in peas, there are only 2 \ parts of heat-givers, 

 reckoned as starch. One pound of peas contains 

 flesh-formers equal to 3^ oz. of the dry nitrogenous 

 matter of muscle or flesh. According to Frankland, 

 i Ib. of dry peas, when digested and oxidized in the 

 body, might liberate force equal to 2,341 tons raised 

 i foot high. The greatest amount of external work 

 which it could enable a man to perform is 468 tons 

 raised I foot high.'* 



FIELD, BROAD, or WINDSOR BEANS, the seeds of 

 Faba vulgaris, Mcench (= Vicia Faba, L.), a native of 

 Persia, are also eaten when unripe. Large quantities 

 are imported, in addition to those of home-growth, as 

 food for horses. 



FRENCH, or KIDNEY BEANS are the unripe seed- 



* Church, ' Food,' p. 83. 



