64 THE HUMAN BODY. 



ton of the organs of the Body, and this finer supporting 

 meshwork the skeleton of the tissues. Besides forming a 

 support in the substance of various organs, the connective 

 tissues are often laid down as a sort of packing material in the 

 crevices between them ; and so widely are they distributed 

 everywhere from the skin outside to the lining of the alimen- 

 tary canal inside, that if some solvent could be employed 

 which would corrode away all the rest and leave only these 

 tissues, a very perfect model of the whole Body would be left; 

 something like a " skeleton leaf," but far more minute in its 

 tracery. 



The Bony Skeleton (Fig. 16). If the hard framework 

 of the Body were joined together like the joists and beams of 

 a house, the whole mass would be rigid; its parts could not 

 move with relation to one another, and we should be unable 

 to raise a hand to the mouth or put one foot before another. 

 To allow of mobility the bony skeleton is made of many sepa- 

 rate pieces which are joined together, the points of union be- 

 ing called articulations, and at many places the bones enter- 

 ing into an articulation are movably hinged together, forming 

 what are known &s joints. The total number of bones in the 

 Body is more than two hundred in the adult; and the number 

 in children is still greater, for various bones which are dis- 

 tinct in the child (and remain distinct throughout life in 

 many lower animals) grow together so as to form one bone in 

 the full-grown man. The adult bony skeleton may be de- 

 scribed as consisting of an axial skeleton, found in the head, 

 neck and trunk; and an appendicular skeleton, consisting of 

 the bones in the limbs and in the arches (u and s, Fig., 16) 

 by which these are carried and attached to the trunk. 



Axial Skeleton. The axial skeleton consists primarily 

 of the vertebral column or spine, a side view of which is rep- 

 resented in Fig. 17. The upper part of this column is com- 

 posed of twenty-four separate bones, each of which is a ver- 

 tebra. At the posterior part of the trunk, beneath tjie 

 movable vertebrae, comes the sacrum (8 1), made up of five 

 vertebrae, which in the adult grow together to form one bone, 

 and below the sacrum is the coccyx (Co 1-4), consisting of 

 four very small tail vertebrae, which in advanced life also 

 unite to form one bone. 



On the top of the vertebral column is borne the skull, 

 made up of two parts, viz., a great box above which incloses 



