3i8 OF THE GROWTH, &c. 



when the foetus acquires more ftrength, it per-- 

 petually changes its pofition, as we learn from 

 the following obfervations made by perfons {kil- 

 led in the art of midwifery : i. The umbilical 

 cord is often twifted round the body and mem- 

 bers of the child, in a manner that neceffarily 

 fuppofes different motions 'and pofitions. 2. Mo- 

 thers feel the motion of the child fometimes on 

 one fide of the uterus, and fometimes on the o- 

 ther ; and it often ftrikes againft many different 

 places, which could not happen unlefs it affumed 

 different pofitions. 3. As the foetus fwims in a 

 fluid which furrounds it on all fides, it may ea- 

 fily turn, extend, and twift itfelf by its own 

 powers : It rar-ft like wife take different fituations, 

 according to the various attitudes of the mo- 

 ther's body ; vvhen the mother, for example, 

 lies down, the pofition of the foetus muft differ 

 from what it is when ihe ftaiids. 



Moft anatomifts maintain, that the foetus is 

 obliged to bend its body, becaufe it is too much 

 confined by the membranes. But this opinion 

 feems not to be well founded ; for, during the 

 lirft five or iix months, at leaft, there is room 

 more than fufficient to admit a full extenfion of 

 the foetus ; and yet, during all this period, the 

 foetus is bended. Wc fee likewife that the 

 chick is bended in the liquor of the amnios, 

 while, at the fame time, this membrane, and the 

 fluid it contains, afford room fufficient to hold a 



body five or fix times larger than the foetus. We 



may, 



