[FOR THE USE OF MEMBERS. | 
Ropal Institution of Great Britatir, 
1853. 
WEEKLY EVENING MEETING, 
Friday, May 6. 
Ricut Hon. Baron Parks, in the Chair. 
Dr. Lyon Puayrair, C.B., F.R.S. 
On the Food of Man under different Conditions of Age and 
Employment. 
Tue Author commenced by adverting to our very imperfect ac- 
quaintance with the statistics of Food. We are still ignorant 
regarding the quantity of the different proximate constituents of 
Aliment necessary for Man’s sustenance, even in his healthy and 
normal condition. If the question were asked — How much carbon 
should an adult man consume daily ?—there would be scarcely 
more than one reliable answer, viz., that the soldiers of the body- 
guard of the Duke of Darmstadt eat about 1loz. * of carbon in the 
daily supply of food. 
If again the question were asked — How much flesh-forming 
matter supports an adult man in a normal condition? — no positive 
answer could be given. Even, as respects the relation between 
the carbon in the flesh-forming matter and that of the heat-givers, 
we have no reliable information. It is true that certain theoretical 
conclusions on this head have been drawn from the composition of 
flour, but no real statistical answer deduced from actual ex- 
perience exists. 
When we inquire into the cause of our ignorance on these points, 
it is found that the progress to knowledge is surrounded with 
difficulties. Neither chemistry nor physiology is in a sufficiently 
advanced state to grapple satisfactorily with the subject of nutrition. 
For example, we know that albumen in an egg is the starting-point 
for a whole series of tissues; that out of the egg comes feathers, 
claws, fibrine, membranes, cells, blood corpuscules, nerves, &c., 
but only the result is known to us; the intermediate changes and 
their causes are quite unknown. After all, this is but a rude and 
unsatisfactory knowledge. Hence, when we approach the subject 
* Licbig states it a higher amount, but this is a recalculation from the new 
food tables. 
No. 16, Z 
