762 THE POPULAR SCIENCE MONTHLY. 



are never transgressed in its natural motions. Everything takes place 

 in souls as though there were no body, and in the body everything 

 takes place as though there were no soul." 



Lord Bacon accepted the doctrine of " vital spirits " as applied to 

 both animate and inanimate bodies. 



Glisson believed in " vital spirits intermediate between the soul and 

 organs," and regarded " irritability as a force of which perception and 

 appetite are factors." 



Stahl, in the eighteenth century, enunciated the doctrine that 

 chemical forces and vital force not only differ from each other, but are 

 antagonistic. Chemical forces are destructive of the living body, and 

 are held in abeyance, and their disintegrating power is neutralized by 

 a vital force which resides in the body and ministers to its functions. 

 " This vital force, struggling against physical force, acts intelligently, 

 upon a definite plan, for the preservation of the organism " ; its tri- 

 umph secures life, while the rule of the physical forces alone brings 

 death. The theories of " vitalism " and " animism " thus took their 

 places among the philosophic ventures of the age. 



Borden, Barthez, and Grimaud, " representing the school of Mont- 

 pellier," accepted " vitalism " but rejected " animism." The principle 

 of life was believed to be distinct from the soul, though it was thought 

 to operate independently of mechanical or chemical laws. 



Haller inaugurated the inductive method in physiological science, 

 and, by experiments, located irritability in the muscular tissue and 

 sensibility in the nervous tissue. 



Buffon explained vital phenomena through the instrumentality of 

 " organic molecules " which, differing in form and nature, were inde- 

 structible and endowed with the "properties of vitality." These 

 molecules, when associated, not only gave specific character to each 

 part of the organism, and provided for its physiological activity, but 

 became the perennial source of life. 



In order to explain how the organic molecules became arranged 

 into the specific forms of life, and preserved individual and type iden- 

 tity in nutrition and reproduction, Buffon projected his theory of " in- 

 terior molds," by which, in connection with the " organic molecules," 

 he sought to account for all the phenomena of the organic world. It 

 was not until 1827, when the ovule in the ovarian follicle of mamma- 

 lians was discovered by De Baer, that the theory of " organic mole- 

 cules " and " interior molds " was overthrown. A single demonstrated 

 fact destroyed the speculations of an age. 



Bonnet's theory of " included germs " was another example of rea- 

 soning from premises that had not been verified, and the result was 

 disastrous to the subjective method. He taught that the germs of all 

 life-forms not only pre-existed in their first-created representative, but 

 actually contained within themselves, already formed, all the parts of 

 the future organism. 



