Mathematical Theories of the Earth. — Woodward. 283 
to the impression of contentment with and acquiescence in the results 
of science, which seems to find easy access to trained as well as un- 
trained minds before an investigation is half completed or even fairly 
begun. That some such tacit persuasion of the completeness of the 
knowledge of the earth has at times pervaded scientilic thought, there 
can be no doubt. This was notably the case during the period which 
followed the remarkable epoch of Laplace. The profound impression 
of the sufficiency of the brilliant discoveries and advances of that 
epoch is aptly described by Carlyle, in the half humorous, half sar- 
castic language of Sartor Resartus. "Our Theory of Gravitation," he 
says, "is as good as perfect: Lagrange, it is well known, has proved 
that the Planetary System, on this scheme, will endure forever; La- 
place, still more cunningly, even guesses that it could not have been 
made on any other scheme. Whereby, at least, our nautical Logbooks 
can be better kept ; and water transport of all kinds has grown more 
commodious. Of Geology and Geognosy we know enough ; what with 
the labors of our Werners and Huttons, what with the ardent genius 
of their disciples, it has come about that now, to many a Royal Soci- 
ety, the creation of a World is little more mysterious than the cooking 
of a dumpling; concerning which last, indeed, there have been minds 
to whom the question, Hoiv the apples were got in, presented difficul- 
ties." This was written nearly sixty years ago, about the time that 
the sage of Ecclefechan abandoned his mathematics and astronomy 
for literature to become the seer of Chelsea, but the force of its irony 
is still applicable for we have yet to learn essentially, "how the ap- 
ples were got in," and what kind they are. 
As to the future, we can only guess, less or more vaguely, from our 
experience in the past and from our knowledge of present needs. 
Though the dawn of that future is certainly not heralded by rosy 
tints of over confidence amongst those acquainted with the difficulties 
to be overcome, the prospect, on the whole, has never been more 
promising. The converging lights of many lines of investigation are 
now brought to bear on the problems presented by our planet. There 
is ample reason to suppose that our day will witness a fair average of 
those hai)py accidents in science which lead to the discovery of new 
principles and new methods. We have much to expect from the 
elaborate machinery and perfected methods of the older and more 
exact sciences of measuring and weighing — astronomy, geodesy, phys- 
ics and chemistry. We have more to expect, perhaps, from geology 
and meteorology, with their vastaccumulation of facts not yet fully cor- 
related. Much, also may be anticipated from that new astronomy 
which looks for the secrets of the earth's origia and history in nebulous 
masses or in swarms of meteorites. We have the encouraging stimulus 
of very general and rapidly growing popular concern in the objects of our 
inquiries, and the freest avenues for the dissemination of new informa- 
tion ; so that we may easily gain the advantage of a concentration of 
energy without centralization of personal interests. To tho.se, there- 
