The Skeleton. 3 



For the agriculturist an elementary knowledge of com- 

 parative anatomy is essential, because owing to the differ- 

 ences in the construction of the various animals, such 

 animals require different treatment in the way of feeding, 

 watering, shoeing, and during sickness. By the study 

 of anatomy we are enabled to map out the animal, and 

 thus can locate a diseased part more readily. 



The work of the anatomist may be compared to that of 

 the architect, because in both cases the study of the 

 framework is the basis for the study of the superstructure. 



The animal may be briefly analyzed as a bony skele- 

 ton, covered outside by muscles and the skin, and con- 

 taining inside that skeleton the various organs, such as 

 the heart, lungs, liver, kidneys, stomach, intestines, 

 reproductive organs and the nervous system. 



The Skeleton. The framework is generally called the 

 skeleton. It is made up principally of bones. 



Bone is a hard, yellowish white, insensitive body made 

 up of earthy and animal matter. The earthy matter is 

 made up mainly of the following materials: Phosphate of 

 lime, carbonate of lime, phosphate of magnesia, and solu- 

 ble salts. The earthy and animal matters are in the 

 healthy mature animal properly balanced, in the young 

 animal the animal matter is in excess, thus accounting 

 for the small number of breaks (fractures) in young 

 animals, and also for the rapidity with which such break- 

 ages are repaired. In old animals the earthy matter is in 

 excess, consequently breakages (fractures) are more 

 frequent and repair is slower than in the young animal. 



Bone is the hardest of all the animal tissues, due to 

 the presence of the earthy matter before mentioned, its 



