CJtemical Affinities. 71 



on this terrestrial globe, though called into action by opera- 

 tions going on in an object millions of miles off? No. 



Doubtless the sun's calorific rays are identical in nature 

 with that agent on earth, and liberated by chemical action, 

 and known as positive heat or free caloric. By solar caloric 

 the ostrich's egg is hatched, as is the pheasant's by sitting 

 upon it, and so giving off animal heat. 



This agent caloric starts motion in the pip it is the re- 

 pellent to attraction, and the matter in the pip or germ first 

 begins to act and react from the decomposing matter of the 

 pip itself, and, from the vigour gained by this appropriation, 

 new and increasing actions and reactions on matter external 

 to itself now take place ; and these increased actions only 

 cease when every reaction has completed itself according to 

 the stamp given to its first germinal condition when en- 

 tombed in its sarcocarp and epicarp, and every fibre, pith, 

 liber, bark, leaves, and perfect circulation result out of 

 the actions and reactions impressed upon the form of matter 

 agglomerated together in the germinal spot contained in 

 the pip, and first nourished by its own decaying matter, which 

 is suitable pabulum for aiding actions and reactions in each 

 upon the other from the first germinal agglomeration to the 

 perfect fruit-bearing apple-tree, etc. 



But it will be said, How are we to account for the doctrines 

 of Morphology ? It is by the action and reaction of repulsion 

 and attraction, in the form of specific fluids of a purely 

 interpenetrating character, that we are to account for the 

 endless changes in matter adverted to in the manifestations 

 of a tree's growth and decay, arising out of the stamp of the 

 first germinal impression. 



Or are we to say that the law of Precursion deter- 

 mines every pliant movement in the axial changes of 

 a bud from the leaves to the petals, stamens, anthers, 

 pistils, stigma, pollen dust, and granules on to the germ, 



