A HARD-WORKING DIET. 361 



Such vegetables as cabbages and carrots contain so 

 large a proportion of water about 90 per cent. they 

 cannot be looked upon as sources of either nitrogen or 

 carbon compounds, as the quantities that would have 

 to be eaten are enormous. A pound of cabbage gives 

 no more muscle-forming material than rather less 

 than a quarter of an ounce of meat. Sixteen pounds 

 of cabbage would furnish only as much as a quarter 

 of a pound of meat. Vegetables have, however, other 

 valuable uses. 



It may perhaps seem that a difficulty arises in 

 regard to this table in working out the connection 

 between these nitrogen compounds (which contain 

 C H O N) and the carbon compounds (which con- 

 tain C H O) see p. 356 with the figures given on 

 p. 354. C 4,900, N 300. A table is given at the 

 end of this handbook for helping calculations as to 

 the amount of N present in N compounds. As ex- 

 plained in the pages previous to p. 348, it is only by 

 getting at the quantities of the elements taken in and 

 given off in different forms we can know what chemi- 

 cally takes place within our bodies. Recollecting 

 what was mentioned on p. 358 about nitrogenous com- Can we 



obtain our 



pounds, it seems highly important to look at the nitrogen 

 amount of N present in foods used in a hard-working from fish? 

 diet. In this next table they are therefore given in 

 single column. Meat and fish are compared, for if, 

 as seems not improbable, " The roast beef of old Eng- 

 land " is to become merely a tradition, and the cheery 

 song preserved as a curiosity among the ancient 

 music in libraries, then it may be useful to know what 

 fish most nearly correspond in the amounts of nitrogen 



