Geological Society. 305 



allow, that the primary laws of nature are immutable that all we 

 now see is subordinate to those immutable laws and that we 

 can only judge of effects which are past, by the effects we behold in 

 progress. Whether there be, or be not, any physical traces of a state 

 of things anterior to the commencement of our geological series of de- 

 posits, is a question of no real importance. But to assume that the 

 secondary combinations arising out of the primary laws of matter, have 

 been the same in all periods of the earth, is, I repeat, an unwarrant- 

 able hypothesis with no a priori probability, and only to be main- 

 tained by an appeal to geological phenomena. 



Jf the principles I am combating be true, the earth's surface ought 

 to present an indefinite succession of similar phaenomena. But as far 

 as I have consulted the book of nature, I would invert the negative 

 in this proposition, and affirm, that the earth's surface presents a 

 definite succession of dissimilar phaenomena. If this be true, and 

 we are all agreed that it is j and if it be also true, that we know no- 

 thing of second causes, but by the effects they have produced 5 then, 

 " the undeviating uniformity of secondary causes," the <( uniform 

 order of physical events," " the invariable constancy in the order 

 of nature," and other phrases of like kind, are to me, as* far as regards 

 the phaenomena of geology, words almost without meaning. They 

 may serve to enunciate the propositions of an hypothesis ; but they 

 do not describe the true order of nature*. 



Each formation of geology may have required a very long period 

 for its complete development ; and of such an element as past time, 

 we grudge no man the appropriation. But after all, the successive 

 formations, about which we speculate, however complex in their sub- 

 divisions, are small in number: and after deciphering a series of 

 monuments, we reach the dark ages of our history, when, having no 

 longer any characters to guide us, we may indulge at will in the crea- 

 tions of our fancy. We may imagine indefinite cycles, and an indefi- 

 nite succession of phaenomena j and in the physical world, as well as 

 in the moral, we may have our long periods of fabulous history. But 

 these things belong not to inductive geology ; and all I now contend 

 for is that in the well established facts brought to light by our in- 

 vestigations, there is no such thing as an indefinite succession of 

 phaenomena. 



I will not, even in imagination, travel with you over the succes- 

 sive formations of the earth, or point out their mineralogical di- 

 stinctions ; but I may remind you, that in the very first step of our 

 progress we are surrounded by animal and vegetable forms, of 

 which there are now no living types. And I ask, have we not 

 in these things some indication of change and of an adjusting 

 power altogether different from what we commonly understand by 

 the laws of nature? Shall we say with the naturalists of a former 

 century, that they are but the sports of nature ? Or shall we adopt 

 the doctrines of spontaneous generation and transmutation of spe- 

 cies, with all their train of monstrous consequences ? These sub- 



* Principles of Geology, p. 75, 76, 86, &c. &c. 



N.S. Vol. 9. No. 52. April 1831. 2 R jects, 



