INTRODUCTORY OBSERVATIONS, xxxl 



fparent vifcous fluid, furrounding a yellow liquid 

 c6ntained in another envelope ; nothing more 

 is vifible. If the egg is expofed to heat, it is of 

 no importance whence derived ; if attaining a 

 certain degree, appears an irregular vermicular 

 figure, without any determinate parts. But this 

 is the rudiments of the chicken. A red point 

 next becomes vifible, which is the heart : then 

 the eyes and the bill are unfolded : the embryo 

 gradually increafes ; it grows a perfedt animal, 

 andburfts the Ihell. In a manner nearly analogous 

 are the original evolution and increment of the hu- 

 man living foetus. A tranfparent veficle is detach- 

 ed from the ovary by impregnation ; it is depofited 

 in the womb j all the parts of the human body 

 appear ; and what is in one and twenty days ac- 

 complifhed in the chicken fucceeds in nine 

 months : the perfedl fcetus is formed. How 

 this could be affeded without any fenfible pri- 

 mordium, confounded naturalifts, (for then it 

 had not been proved that the germ belongs to 

 the female) and when they faw a living animal- 

 furnifhed by the male, they eagerly adopted it aa 

 the principle of exiftence. 



III. Death of Animals in Stagnant 

 Air. — Long before philofophical experiment, it 

 was probably well known, that the life of an ani- 

 mal confined where there is no admilTion of frefh 



air., 



