112 PHYSIOLOGY CHAP. 



the metabolism of a vegetarian married couple, an engineer aged 

 49 and his wife aged 48 years. From 1883 to 1891 the engineer 

 lived on cooked vegetables, with milk, eggs, cheese, and butter. 

 From 1891 to 1903 he adopted a strictly vegetable diet, to which he 

 adhered during the experiments made by Caspari. His wife had 

 lived on a mixed diet until the end of 1899, when she took to the 

 same strictly vegetarian diet as her husband, and adhered to it 

 during the investigations. 



These investigations lasted five days, from the 5th to the 9th 

 of February 1902, during which the engineer took active muscular 

 exercise, and performed certain gymnastics. His food consisted 

 of barley-water, sugar, dates, nuts, olives, peeled and cooked 

 potatoes. His wife's diet was the same except that she did not 

 take sugar, but cocoa and cooked carrots instead. The quantity of 

 food taken varied considerably during the five days of the experi- 

 ment. The total quantity consumed in five days by the engineer 

 was 3915 grms. of nitrogen, and 1099*1 fat; in the case of his 

 wife, 26-64 of nitrogen, and 495 of fat. 



The total number of calories, ascertained directly by com- 

 bustion, was 22796 for the engineer, 13573 for his wife. 



The daily 'averages were respectively : 



Nitrogen 7'83 grms. Fat 219-8 grms. Calories 4559. 



5'33 99 2715. 



The averages per day, and per kilo, body- weight, were : 



Nitrogen 0'114 grm. Calories 66. 



0092 47. 



Of the food taken the amounts utilised were respectively : 



Nitrogen 73 - 79 per cent. Fat 88-49 per cent. Calories 91-11 per cent. 



75-79 89-92 92-93 



The engineer during the five days retained 5 '20 grms. of nitrogen 

 = 156 grms. of flesh ; his wife 2-45 grms. of nitrogen = 73 '5 of flesh. 

 He gained 800 grms. in weight ; his wife 900 grms. 



Caspari, after summing up all the scientific researches which 

 have been made into this subject, concludes that they undoubtedly 

 teach us that a purely vegetable diet, even a raw one, " is capable 

 of keeping a young and vigorous organism at the highest level of 

 bodily and mental activity and capacity for work." 



A searching and accurate examination of the drawbacks and 

 advantages of vegetarianism as compared with those of a mixed 

 diet will readily give the following results : 



(a) The sum total of empirical observations and scientific 

 investigations of a purely vegetable diet afford manifest proof that 

 vegetable foods in general are less fully utilised than animal foods ; 

 a smaller quantity of the nutritive substances contained in them 



