THE PAL^TIOLOGICAL SCIENCES. 533 



are very different, in the branches of knowledge 

 which I have thus classed together. The natural 

 features of the earth's surface, the works of art, the 

 institutions of society, the forms of language, taken 

 together, are undoubtedly a very wide collection of 

 subjects of speculation ; and the kinds of causation 

 which apply to them are no less varied. Of the 

 causes of change in the inorganic and organic 

 world, the peculiar principles of geology, we 

 shall hereafter have to speak. As these must be 

 studied by the geologist, so, in like manner, the 

 tendencies, instincts, faculties, principles, which 

 direct man to architecture and sculpture, to civil 

 government, to rational and grammatical speech, 

 and which have determined the circumstances of 

 his progress in these paths, must be in a great 

 degree known to the palsetiologist of art, of society, 

 and of language, respectively, in order that he may 

 speculate soundly upon his peculiar subject. With 

 these matters we shall not here meddle, confining 

 ourselves, in our exemplification of the conditions 

 and progress of such sciences, to the case of 

 geology. 



The journey of survey which we have attempted 

 to perform over the field of human knowledge, 

 although carefully directed according to the paths 

 and divisions of the physical sciences, has already 

 conducted us to the boundaries of physical science, 

 and gives us a glimpse of the region beyond. In 

 following the history of life, we found ourselves led 



