INORGANIC ELEMENTS OF FOOD. 



415 



trough in the course of the day, I found that it amounted to about 

 770 grains troy. 



Notwithstanding these facts, it is still doubtful whether the lime 

 contained in ordinary well-water would prove sufficient to supply a 

 growing animal with the material requisite to the formation of its 

 bones ; in adults, indeed, changes in the elements of the bones ap- 

 pear to proceed so slowly that a very small quantity of calcareous 

 matter probably suffices to repair losses ; but it is otherwise with 

 young and growing animals. I have shown that a calf six months 

 old receives with its forage a quantity of phosphoric acid which cor- 

 responds to 555.7 grains of phosphate of lime. A calf a few week.s 

 old, when it has 17 or 18 pints of milk per diem, receives 802.7 

 grains of mineral substances, into which subphosphate of lime or 

 bone earth enters in the proportion ot 370.5 grains. It would be in- 

 teresting to ascertain what quantities of these substances were as- 

 similated by so young an animal, and at a period when the growth 

 is so rapid that the increase from day to day sometimes exceeds 2 

 pounds. 



The importance of the inorganic principles of the food once re- 

 cognised, it concerns us to take note of their nature and quantity in 

 the ratio we allow to our domestic animals. It is in fact this con- 

 sideration which has led me to determine the quantities of phospho- 

 ric acid and lime contained in the various articles of food the ashes 

 of which have been analyzed. With these data the proportion of 

 bone earth contained in a given ration is forthwith perceived. 



One thousand parts of the forage gathered at Bechelbronn in its 

 ordinary state contained : 



Hay 



Potatoes 



Beet 



Turnip 



Jerusalem Potato 



Wheat 



Maize 



Oats 



Wheat-straw — 



Oat-straw 



Ciover-hay 



Peas 



Haricots 



Beans 



We seem here to observe a certain relation between the proportion 

 of azote ard that of the phosphoric acid contained in the food ; the 

 most highly azotized are also those that generally contain the largest 

 quantity of the acid, a circumstance which seems to indicate that in 

 the vegetable kingdom the phosphates are connected more especially 

 with the azotized principles, and that they accompany them in pass- 

 ing into the textures of animals. With the assistance of the above 

 table it is easy to ascertain the quantity of phosphate of lime which 



