68o Dietaries of Labouring Prisoners in Indian Jails. [part iv. 



CHAPTER V. 



SUMMARY AND CONCLUSIONS. 



72. As it has been necessary to enter into so many details in connection with 

 these prison dietaries, it may be desirable that a summary should be prepared of the 

 salient points of the memorandum. Discussion of abstruse physiological questions has 

 been, so far as possible, avoided, but the question as to what constitutes the essential 

 alimentary principles of a dietary suitable for native labouring prisoners could not be 

 satisfactorily examined without a brief reference to some of the more recent researches 

 which have been made on the subject, and which have, more or less completely, 

 reversed the views on important points previously entertained by most writers on 

 dietetics. It has been pointed out that, owing principally to the teachings of Liebig, very 

 great prominence has been given to the necessity of increasing the albuminoid or 

 nitrogenous principle of food in proportion to the amount of work exacted, on the 

 supposition that the nitrogenous, chiefly muscular, tissues of the body are rapidly 

 wasted as a result of exertion, and that the non-nitrogenous elements of food (starch, 

 sugar, fat, etc.) were simply useful in the production of heat. 



73. This conception has obtained such a firm hold on popular opinion that nearly 

 all the recommendations as to improving the dietary referred to in the preceding chapters 

 are, consciously or unconsciously, based on it — an addition to the nitrogenous principles 

 of the diet being the prominent feature advocated. So long ago as 1845 it was 

 maintained by Mayer that " a muscle is only an apparatus by means of which the 

 transformation of force is effected, but that it itself is not the material by the change 

 of which the mechanical work is produced." The correctness of this statement is 

 now generally allowed, and further research has established that nearly all the motion, 

 as well as the heat of the body, is dependent on the combustion within it of the 

 carbonaceous principles of the food ; whereas one of the chief uses of the nitrogenous 

 principles is to serve as the pabulum from which the tissues are developed and 

 renovated. The precise character of the changes which take place is still a disputed 

 question ; but it may serve as a help to the comprehension of this phase of the subject, 

 even though the comparison be not scientifically accurate, were these living tissues 

 of the body looked upon as the wick in the interstices of which* the products of 

 carbonaceous material undergo chemical change — are in fact burnt — so as to set free 

 the energy stored up in them. This change is incessantly taking place in the body 

 in order to generate the heat and motion requisite for the maintenance of life, 

 but, in order to withstand the influence of severe cold, or to perform extra 

 labour, the process is accelerated. The more energetically this change proceeds the 



* Whether in the cells of the tissue or in the lymph in which they are bathed, need not be specially 

 consid^ed here. 



