of Edinburgh, Session 1870-71. 
377 
forces of parturition is one that has been much discussed and for 
a long time. The great Haller, indeed, held opinions which are 
in accordance with Haughton’s view. This renowned physiologist 
discarded the opinion common in his day, and now almost uni- 
versally entertained, that the uterus is the main source of the power 
exerted in every stage of parturition. 
Haughton gives us no reason for discrediting the general opinion 
of obstetricians, relying apparently on his conclusions alone re- 
garding the comparative power of the two forces, that of the uterine 
muscle and that of the assistant voluntary muscles. No doubt he 
makes some observations intended to be corroborative as to the 
economy of force and other so-called laws of nature ; but such 
reflections cannot be regarded otherwise than as premature by 
those who, like myself, do not adopt this writer’s conclusions upon 
whose verity their justice depends. 
In the course of his concise view of this question in his work on 
Physiology, Haller twice takes care to express his doubts as to the 
truth of his own opinions ; and he ends by appealing to anatomists 
for light upon the subject. This appeal is, at least, ingenuous, for 
his argument against the ordinary opinion rests greatly upon the 
uterine fibres, their direction, and the direction of the force evolved 
by them ; and, as Haller’s notions on this anatomical point were 
very imperfect, and his mechanical ideas equally so, we need attach 
no weight to this part of his argument. Besides this, however, he 
has really nothing deserving the name of good evidence on his 
side. He thinks the effects produced by expulsive pains greater 
than the power of the uterus ; but this is evidently mere begging 
the question. So also is his dependence, for aid in his judgment, 
on a picture of the great struggles of the voluntary muscles. 
Authors generally do, as I have said, entertain an opinion 
opposed to that of Haller and Haughton. They are too numerous 
to name, and no one merits special mention; for, so far as I know, 
no one has distinguished himself by the novelty or elaborateness 
of his arguments in support of the ordinary view that the uterus is 
the chief agent in the whole process of parturition, and that the 
voluntary muscles, whether stimulated by volition or by reflex 
excitement, are, in a secondary position, aiding the uterus indeed 
but not supplying the chief force. There is no positive value in an 
