240 SKELETON. 



ing gait, such as may be mimicked, at any time, by walking 

 with the legs in a state of abduction: but, when diminished, it 

 is called knocked knees, and interferes with the firmness of the 

 step by causing the centre of gravity to pass, alternately, through 

 the internal condyles of the ossa femorum, instead of falling ex- 

 actly between them. 



The firmest position in which we can stand is that in which 

 the feet are perfectly straight and parallel with each other, so as 

 to form a square base for the support of the trunk. If from this 

 position the toes be turned either inwards or outwards, the con- 

 sequent reduction of the antero-posterior diameter of the base, 

 causes' less resistance to the natural inclination of the trunk for- 

 wards. Whatever may be the grace and the ultimate intention 

 of the first position in dancing, to wit, that of having the feet 

 nearly in the same line, with the heels touching and the toes out- 

 wards, it is certainly the most unfavourable attitude for ease in 

 keeping the body erect that can be adopted; for the base of sup- 

 port being diminished, both by the length of the body of the os 

 calcis, and by that of the foot, anterior to the ankle joint, the 

 trunk is continually inclining either forwards or backwards, and 

 is prevented from falling only by the alternate action of the 

 muscles behind and in front. 



When we are upon the knees, the base of support for the 

 trunk being entirely withdrawn in front, it is necessary, in order 

 to maintain the position, and to prevent falling forwards, that 

 the hip joint be flexed so as to throw the weight of the body en- 

 tirely behind the thigh bones. The position is one of so much 

 restraint and fatigue upon the muscles, that it can be maintained 

 for a long time, only by some artificial support in front, or by 

 the buttocks falling down upon the legs, and resting against them. 



The position we assume on being seated in a chair, is the 

 easiest of any of those in which the trunk is kept erect, or nearly 

 so. The length of the lever, represented by the whols length of 

 the skeleton, is then diminished one-half; consequently, any pre- 

 ponderance of it at particular points, above, bears with less force 

 upon the base. The base itself is much augmented by the ampli- 

 tude of the buttocks, and by the horizontal position of the thigh 





