x CONTENTS 



ON THE CANCELLATED STRUCTURE OF SOME OF 

 THE BONES OF THE HUMAN BODY 



Very little attention given in works on anatomy to this sub- 

 ject with reference to the weight they have to sustain . , 99 



Sir Charles Bell's allusion to the direction of the cancelli 

 in the neck of the thighbone not satisfactory; those of the 

 astragalus and os calcis are accurately described and fig- 

 ured 100, 101 



Inferences drawn from the direction of the cancelli are that 

 they are to sustain weight, and in some cases have re- 

 ference to the erect position which is naturally assumed by 

 man alone 103 



I. VERTEBRAE 



Their functions a^e the support of weight, and to constitute a 

 series of levers for the application of muscular force . . 103 



Fig. 29, showing direction of cancelli in plan where the pres- 

 sure is greatest 104 



II. NECK OF THE THIGHBONE 



Whole weight of the head, trunk, arms, and pelvis rests on 

 the two heads of thighbones 105 



Size of angle which the neck makes with the shaft of the 

 femur. Bourgery and Jacob's description of cancelli con- 

 fused ; in his Fig. 31 is represented an archway which does 

 not exist 107, 109 



Author's views, with his cancelli, Fig. 30 110 



Mr. Ward approaches nearer the truth, Fig. 31; but his repre- 

 sented archway does not exist Ill 



The cancelli of the bones as braces 112 



III. THIGH 



Its structure and the braces which support it 114 



IV. ASTRAGALUS 



Sustains in each foot one half the weight of the body, or the 



whole of it when it is supported on one foot 114 



Description of astragalus 115 



