ARTICULATIONS OF THE BONES. 11? 



Water, 80.46 98.3 



Fibrous matter, 



Albumen, 



Gelatine and Mucilage, 



Muriate of Soda, 



Soda, 



Phosphate of lime, 



100.00 99.99 

 Margueron *, J. Davy (. 



Besides the sheath formed by the continuation of the pe- 

 riosteum, and which is too slender to retain the bones in 

 their proper place, the joints are furnished with ligaments. 

 These are membranes of a dense fibrous texture, flexible, 

 elastic, and possessed of great tenacity. They have their 

 insertion in the periosteum and bone, with which they are 

 intimately united. When they follow the course of the pe- 

 riosteum, and form a sheath round the joint, they are term- 

 ed capsular. When they occur as broad belts on the sides 

 of the joint, they are called lateral ; and when they pass 

 from one articular surface, like a cord, into the other, they 

 are called central Their composition has not been investi- 

 gated with care. It is probable that they approach the 

 nature of cartilage. They serve to secure the joints from 

 dislocation- an accident that can scarcely happen, unless 

 the ligaments be previously lacerated. They likewise, in 

 some cases, furnish a basis for the origin or insertion of 

 muscles. 



The motions which joints of the kind are capable 

 of performing, may be reduced to three kinds flex- 

 ion, twisting, and sliding. In flexion, the free extre- 

 mity of the bone which is moved, approaches the bone 



* Annales de Chimie, xiv. 127. 



-f* MONRO'I Outlines of Anatomy, i. p. 82. 



