122 SWINE 



throughout the body. Approximately two to three per 

 cent of the live weight of the hog is composed of this kind 

 of material. The ash or mineral matter in general of any 

 vegetable material is that which is left after it is burned 

 as, for instance, the ashes taken from a wood stove. 

 Bones are made up principally of two kinds of material, 

 namely, ash or mineral matter and protein. To demon- 

 strate to one's own satisfaction the amount of these two 

 substances present, the bone may be put into a fire and 

 thoroughly burned. This will take out the vegetable mat- 

 ter, such as the protein and leave the mineral matter. 

 The bone after being taken from the fire will be brittle, 

 light and porous, which is the mineral matter of the bone. 

 If the mineral matter is to be taken out and the protein 

 left, the bone should be placed in some acid for a time 

 which will dissolve the ash and leave the protein. The 

 bone in this condition will be soft and pliable. There are 

 various kinds of mineral substances in the general ash of 

 the body, all of which must be supplied for the proper 

 development of the animal. 



