460 HISTORY OF PHYSIOLOGY. 



the embryo pre-existed in the mother, before any union of the sexes. 

 It is easy to see that this doctrine is accompanied with great difficul- 

 ties; 12 for if the mother, at the beginning of life, contain in her the 

 embryos of all her future children ; these embryos,again must contain 

 the children which they are capable of producing ; and so on indefi- 

 nitely; and thus each female of each species contains in herself the 

 germs of infinite future generations. The perplexity which is involved 

 in this notion of an endless series of creatures, thus encased one within 

 another, has naturally driven inquirers to attempt other suppositions. 

 The microscopic researches of Leeuwenhoek and others led them to 

 the belief that there are certain animalcules contained in the seed of 

 the m'ale, which are the main agents in the work of reproduction. 

 This system ascribes almost everything to the male, as the one last 

 mentioned does to the female. Finally, we have the system of Buf- 

 fon ; the famous hypothesis of organic molecules. That philosopher 

 asserted that he found, by the aid of the microscope, all nature full of 

 moving globules, which he conceived to be, not animals as Leeuwen- 

 hoek imagined, but bodies capable of producing, by their combination, 

 either animals or vegetables, in short, all organized bodies. These 

 globules he called organic molecules. And if we inquire how these 

 organic molecules, proceeding from all parts of the two parents, unite 

 into a whole, as perfect as either of the progenitors, Buffon answers, 

 that this is the effect of the interior mould ; that is, of a system of 

 internal laws and tendencies which determine the form of the result 

 as an external mould determines the shape of the cast. 



An admirer of Buffon, who has well shown the untenable character 

 of this system, has urged, as a kind of apology for the promulgation of 

 the hypothesis, 14 that at the period when its author wrote, lie could 

 not present his facts with any hope of being attended to, if he did not 

 connect them by some common tie, some dominant idea which might 

 gratify the mind ; and that, acting under this necessity, he did well to 

 substitute for the extant theories, already superannuated and confessedly 

 imperfect, conjectures more original and more probable. Without dis- 

 senting from this view, we may observe, that Buffon's theory, like those 

 which preceded it, is excusable, and even deserving of admiration, so far 

 as it groups the facts consistently ; because in doing this, it exhibits 

 the necessity, which the physiological speculator ought to feel, of 

 aspiring to definite and solid general principles ; and that thus, though 



11 Bourdon, p. 204. 12 Ib. p 20. J3 Ib. p. 219. ' 4 Ib. p. 221. 



