NOTES AND QUERIES. 
407 
geological inferences, iiupro])Crly so called, liave rather provoked merriment than 
scrions attention, wliich, combineil witli tiic habit of assumin"; no very probable 
conjectures for demons! rable truths, has rendered Geolo2;y somcwliat unpopular 
oven among professed nien of science; and the term "logic of geology," or some- 
thing similar, expressive more of ironical contempt than anxious expectation, 
or even the j)resent condition of the science. But, throwing off every hasty 
habit, and discarding every hasty generalization, tile student of geology will 
truly progress ; for their's is a science happily capable of plulosophical inference, 
and cue which will amply repay the stndy devoted to it. I. A. Davies. — At 
aU times we give insert ion to any sensilile remarks, whether they convey informa- 
tion or pourtray doubts or niis-comprchensions for solution. A wrong im- 
pression produced on one reflecting mind by a want of full information, or a 
wrong reading, or misunderstanding of abstruse facts may be produced on other 
minds in a like manner ; and it is obviously one of the duties of a popular 
magazine on a special science at all times and on all occasions to set right its 
humbler votaries wheucver any of them are doubtful or take a wrong view. 
Geologists well versed in the science would perceive at a glance some erroneous 
notions mixed up with our correspondent's not in-acute remarks ou geological 
logic, but these points might not oe so palpable to general readers. 
There is no reason why Geology should not become ultimately one of the 
most logical of all the sciences, of which indeed it is a grand and wonderful 
combination, and consequently inherently partakes of all their mathematical 
and logical properties. But while geology is in so thoroughly progressive a 
state, completely logical deductions should not be ex})eetedto be produced from 
admittedly defective data. Upon insecure foundations no one can properly 
buOd up logical conclusions. We admit, however, that much that seems 
illogical hi the WTitings of some modern geologists, might have presented a very 
difl'ereut aspect by a little care on the part of those authors, and we have akeady 
referred to this carelessness of diction which tends to stamp our science with a 
want of logic. This is, however, only ajiparent and not real. The great doctrines 
of Geology based ou a good ground-work of established facts are undoubtedly 
most logically deduced ; and iliere is certainly nothing to prevent every minor 
detail, so aided as geology must ever be by chemistry, mathematics, natural 
physics, and other exact and deductive sciences, being as exact and definite. It 
IS only just, therefore, to conclude that geology, a science compounded of exact 
and logical sciences, should be, if properly compounded, an exact and logical 
whole. 
Now our correspondent, in his own example of reasoning, has gone wi'oug 
altogether in his facts chosen as a basis of attack upon geologists for want of 
logic. Re has first thoroughly mistaken, or is altogether ignorant of the true 
nature and origin of granite. This rock is only a crystallhie condition of rock, 
and in its cryatiilUzed condition may be of any age from older than the Cambrian, 
or lowermost sedimentary rocks, to the newest of the Tertiaries. He is not 
secure again in his statement that no rocks dip into it, if we understand his 
meaning to be that it is totally distmet from any connection with other and 
sedimentary formations ; for certainly sometimes such sedimentary strata, if 
they do not plunge into it as a plank into a heap of mud, which from' the nature 
of things is not to be expected, at least tliev sometimes lose their distinctive 
stratified characters as they approach a granitic boss, and gradually merge into 
its ci-ysfalline and peculiar muicral characters. 
Again, with respect to the vast periods of time required for the formation of 
rock-strata, our correspondent is more illogical himself than any of the geo- 
logists he attacks, for they do carefully take as data those physical phenomena 
which arc going ou around them, and they do moreover in their application 
of those data to past conditions take great care to notice and to observe 
