14 PREFACE. 



act of God, in the work of creation), he supposes the 

 pre-existence of chaos, not, indeed, in the Miltonic 

 sense 



" For hot, cold, moist, and dry, four champions fierce, 

 Strive there for mast'ry, and to battle bring 

 Their embryon atoms, " 



but rather as one vast homogeneous fluid, and even 

 that he suggests not as a historical fact, but as the 

 appropriate symbol of a great fundamental truth. The 

 first effort of magnetic power, the first step from indif- 

 ference to difference, from formless homogeneity to 

 independent existence, is seen in the tranquil deposi- 

 tion of crystals ; and an increasing tendency to difference 

 is observable in the increasing multitude of strata, till 

 we corne to organic life; of which the vegetable and 

 animal worlds may be regarded as opposite poles; car- 

 bon prevailing in the former and azote in the latter ; 

 and vegetation being characterised by the predominance 

 of magnetism in its highest power, as reproduction ; 

 whilst the animal tribes evince the power of electricity, 

 as shown in irritability and sensibility. Passing over 

 the forms of vegetation, we come to the polypi, coral- 

 lines, &c., in which individuality appears in its first 

 dawn ; for a multitude of animals form, as it were, a 

 common animal, and different genera pass into each 

 other, almost indistinguishably. The tubipora of the 

 corals connects with the serpula of the conchylia. In 

 the mollusca the separation of organs becomes more 

 observable ; in the higher species there are rudiments 



