312 ON THE QUANTITY OF FOOD 



observed in March ; owing, probably, to the 

 temperature of the weather being lower in the 

 latter season. 



So far I have given the facts and observations 

 made 40 years since ; I made no deductions from 

 them at the time; indeed the knowledge of 

 animal and vegetable chemistry was at that time 

 in its infancy. Since then the progress of this 

 branch of philosophy has been very considerable, 

 and we are now enabled to approximate, in a 

 good degree, to the quantities of the several 

 chemical elements to be found in the great 

 variety of products of tlie two kingdoms. 



By combining this knowledge with that ob- 

 tained from the preceding facts, we may possibly 

 discover or establish some physiological princi- 

 ples important to be understood in the animal 

 economy, more especially in regard to the ac- 

 quisition and preservation of health. 



From the table we have given, it will appear, 

 that bread and farinaceous vegetables constitute 

 the greatest part of ordinary food. About the time 

 of the above experiments I found that 5 lbs. of 

 flour would make 7 lbs. of bread. Now from 

 the analyses of flour that are given in our systems 

 of Chemistry I think we cannot estimate the 



