164 



ANIMAL MECHANICS. 



result is, that labour ceases until consciousness returns, and 

 enables the ill-treated woman to avail herself of the apparatus 

 of voluntary abdominal muscles provided by nature for her 

 use. 



In these remarks I confine myself altogether to the phy- 

 sical aspects of the use of chloroform in labour, and forbear 

 to express an opinion as to the moral effects likely to be pro- 

 duced by the exhibition of an intoxicating agent, administered 

 merely for the luxurious purpose of deadening the pain of 

 the exercise of a purely natural physiological function. 



g. On the Classification of Muscles and their Mode of 

 Action. — It has been already shown that muscles consist of 

 linear fibres, which may be variously arranged ; and as lines 

 form surfaces, and combinations of surfaces form solids, it is 

 evident that a natural classification of muscles must be essen- 

 tially geometrical, and that the mechanical action of muscles 

 must depend upon their geometrical configuration. 



The following classification of muscles is proposed as a 

 simple and natural arrangement : — 



T. Muscular Fibres lying in the same Plane, 

 i . Fibres parallel and rectilinear. 



(a) Direct Prismatic. 



(b) Ehomboidal. 



(c) Penniform. 



?.. Fibres intersecting and rectilinear. 



(a) Triangular. 



(b) Deltoidal. 



(c) Quadrilateral. 



3. Fibres curvilinear and parallel, 

 (a) Sphincters. 



