196 Siluria. [| April, 
“ That astronomers should congregate to talk of stars and planets, 
chemists, of atoms; geologists, of strata, is natural enough; but 
what is there of equal mutual interest, equally connected with and 
equally pervading all they are engaged upon, which causes their 
hearts to burn within them for mutual communication and un- 
bosoming ? Surely, were each of us to give utterance to all he 
feels, we would hear the chemist, the astronomer, the physiologist, 
the electrician, the botanist, the geologist, all with one accord, and 
each in the language of his own science, declaring not only the 
wonderful works of God disclosed by it, but the delight which their 
disclosure affords bim, and the privilege he feels it to be to have 
aided in it. This is indeed a magnificent induction, a consilience 
there is no refuting. It leads us to look onward, through the long 
vista of time, with chastened but confident assurance that science 
has still other and nobler work to do than any she has yet 
attempted; work which, before she is prepared to attempt, the 
minds of men must be prepared to receive the attempt—prepared, I 
mean, by an entire conviction of the wisdom of her views, the purity 
of her objects, and the faithfulness of her disciples.” 
VI. SILURIA.* 
Grotocy still advances with the rapidity which always character- 
ized the science ; and it needs considerable industry to keep oneself 
au courant with its progress. Sir Roderick Murchison, however, 
even in his old age, not only accomplishes this task, but still assists 
in no small degree to smooth the path and to hasten the march. 
More than this, he is ever foremost in the recognition of the im- 
provements which the allied sciences constantly enable the geologist 
to make; and if he does not always join the ranks of the newer 
school of geologists in more doubtful and theoretical questions, who 
shall say that his opposition does not benefit the science by pre- 
serving his younger brethren from rushing into those speculative 
excesses which have too often proved so detrimental to the attain- 
ment of a true philosophy. 
The most noticeable change in the present edition of ‘ Siluria’ 
is the immense importance acquired of late years by the old gneissic 
rocks, described in the previous edition as the “ Fundamental 
Gueiss” of Sutherland and Ross, which was there treated of as the 
, * ‘Siluria: A History of the Oldest Rocks in the British Isles and other 
Countries ; with Sketches of the Origin and Distribution of native Gold, the general 
Succession of Geological Formations, and Changes of the Earth’s Surface” By Sir 
Roderick Impey Murchison, Bart., K.C.B., D.C.L., LL.D., F-R.S., &e. ‘Fourth 
Edition (including the Silurian System). London: John Murray, 1867. 
