No. 4.] NUTllITION. 59 



Up to this point science has been assiduously applied, and 

 very great progress has been made ; calling, so far as I may 

 judge, rather for a concentration of the information already 

 existing and for its classification in a simple form in order 

 to make it plain to the commonest understanding. Land is 

 now being treated ess as a mine which may be exhausted 

 but more and more as a laboratory or instrument of produc- 

 tion which will respond in its product in proportion to the 

 intelligence with which it is made use of as an instrument 

 rather than as a direct source of production subject to ex- 

 haustion. 



If I am rightly informed, greater progress has been made 

 in Prussia than elsewhere in the classification of land, with 

 such designation of its varying properties as may enable any 

 one to choose the best places for the kind of product that he 

 proposes to work this land upon. 



Lastly, we come to the objective point of all the previous 

 processes with which I have dealt, — to wit, the nutrition of 

 mankind. At this point science seems to have almost 

 stopped. I do not mean to say that there is not a vast deal 

 of thoroughly well-digested scientific information to be found 

 in many great works and in a few lesser or more popular 

 books ; but until very recently there seemed to be no treatise 

 in the Enoflish lano-uao-e that could be brought within the 

 comprehension of the ordinary mind, covering a true method 

 of instruction in the nutrition of mankind ; yet the nutrition 

 of mankind is the simplest of the four forms or directions of 

 the conversion of the forces w^iich I have named. I have 

 endeavored to meet this want by compiling the data supplied 

 by my scientific friends and adding the results of my own 

 somewhat empirical methods. 



Mankind requires fixed proportions of protein, starch and 

 fat, varying but little in their relation to each other ; in the 

 temperate zone varying in quantity rather than in kind, 

 according to the amount of energy required for a given kind 

 of work, as it may be manual, mechanical or mental. Sev- 

 eral ditferent tables of adequate nutrition have been prepared 

 in Germany, in England and in this country. They vary 

 mainly in the ratios of protein and fat, the American ration, 

 so far as it is yet established, calling for a little more fat than 



