448 ON THE PLACE OF FISH IN 



Ibs. ozs. grs. 



burns with a lilac flame. It occurs mainly 



as phosphate and chloride 03 340 



12. Sodium, a metal, the basis of soda, and must be 



kept from the air. It occurs chiefly in union 

 with chlorine as common salt, but also in 

 other compounds and bile .. .. .. o 3 217 



13. Magnesium this metal is found in union with 



phosphoric acid, mainly in bones .. .. o 2250 



14. Iron this metal is essential to the colouring 



matter of the blood. It occurs everywhere 



in the body o o 63 



15. Manganese -, a metal much like iron. Faint 



traces occur in the brain, and decided traces 

 in the blood. 



1 6. Copper traces of this metal are invariably found 



in the human brain, and probably also in the 

 blood. 



Note top. 359. 



It has been suggested that it is the instability 

 the readiness for change of the nitrogen compounds 

 which makes them so serviceable for hard work. All 

 that can be said at present is, that though the facts 

 as to their use seem clear, the explanation has not 

 yet been satisfactorily arrived at. 



Note on Dr. E. Smith! s popular form of putting, the 

 results of his work, p. 368. 



The following is an example of the way in which 

 Dr. E. Smith illustrated that cost and economy in 

 foods are different things. 



Two breakfasts are here selected for comparison, 

 both of the same cost per head (i-^.) while one gives 

 909 grains of carbon and 41 grains of nitrogen more 

 than the other. 



