154 



ANIMAL MECHANICS. 



circumference of a circle to its diameter ; substituting for a 

 and b their numerical values, we find the contents of the 

 uterus to be 402.13 cubic inches. 



The surface of the gravid uterus may be found from the 

 equation — 



Surface = 27r ^ (sin -1 e + y/ j - e 2 ) ; (22) 



in which e is the eccentricity of the generating ellipse. If 

 the numerical values be substituted in this expression, it will 

 be found that the surface of the uterus is 270.66 square 

 inches.* 



Some highly interesting conclusions may be drawn from 

 the preceding calculations, combined with the weight of the 

 total muscular tissue of the uterus. Heschl estimates the 

 weight of the uterine muscles at from 1 lb. to 1.5 lb. Mont- 

 gomery found the muscles of the gravid uterus to weigh 1.5 lb. ; 

 and Levret estimates them at 5 1 cubic inches, which, with a 

 specific gravity of 1.052 (vide p. 84), I find to be equivalent 

 to 1.93 lb. Taking the mean of these estimates, we have — 



Weight of Muscular Fibres of Gravid Womb. 



Heschl, 1.25 lb. 



Montgomery, . . . 1.50 ,, 

 Levret, 1 -93 ».» 



Mean, . . 1.56 lb. 



If we now suppose this quantity of muscle to be spread over 

 the entire surface of the uterus, we find, 



* Levret estimates the contents of the gravid uterus at 438 cubic inches, 

 and its surface at 339 square inches. 



Poppel estimates the contents at 300 cubic inches, and the surface at 2 m 

 square inches. 



