80 
THE GEOLOGIST. 
never advocated theoretical geology : we do not advocate it now. The age of 
geological learning is too yonng for any theories to be put forward which aim 
at completeness, or that do more than indicate the position of a truth, hereafter 
to be found, with greater labour and pains. But deductions from known and 
established facts so insensibly grow into theories when they are treated of, that 
the utmost care has to be used by those who make studies of any branch of 
natund science, lest that which is" hypothetical should be made to pass for a 
truly-based conclusion. And though the domain of the " true and established" 
is o-aining every day somewhat of the treacherous and unstable ground of the 
" uncertain," and so chances of error are diminishing, yet at no time do we be- 
lieve, since geology began to be studied, was there less taste for drawing 
unduly upon the steady gain of honestly-got and costly facts, or a stronger 
feeling among those who are building upon the strong foundation, that the 
wealth of what is real and true should not be perverted to suit a visionary 
scheme, or made to bear witness to what may turn out a false and deluding 
theory. 
These thoughts have occui-red in considering a certain question of great 
interest and importance which has arisen out of the endeavour to classify the 
older Taconic (Cambrian) and Silurian rocks of America. That these Taconic 
rocks are the representatives in the New World of _ the Primordial zone of 
Europe, chiefly developed in Scandinavia and Bohemia, is generally accepted 
among geologists ; while the only hesitation felt is from the fact that these 
Eui-opean "Bottom-rocks" show very scanty traces of life throughout their 
thirty thousand feet of thickness, whereas on the Ameiicau continent they con- 
tain more than one himdi'ed species of crustacean and molluscan life, and are 
indeed nearly as rich in fauna and flora as is the Lower Silurian of Europe. 
In a letter from M. Barrande, of Bohemia, to M. Jules Marcou, of Boston, 
dated August 14, 1860, we find the passage which set us thinking how grandly 
one nation may become interlinked with another, through a scientific discovery 
of harmonies existing between the construction of the continents they inhabit. 
Two European lands — England and Spain — are brought into cousinship with 
Cauada and the States, by similarity of rocks and sympathetic arrangement of 
then- layers ; for M. Barrande has reasonable grounds for his expressed opinion 
that the Taconic schists and limestones of Vermont reproduce in America the 
black shales which lie against the western flank of the Malvern HiUs in our 
own land, and the schisty deposits which hold a similar position with regard to 
the Cantabrian Mountains in Spain. Eor though slight variations and, in the 
western continent, augmentation of animal life occur, yet the position in time 
of the beds is beyond doubt identical ; and we are glad to read M. Barrande's 
remark " that it is a great and noble question, whose final solution wiU com- 
plete the imposing harmonies existing already between the series of Palaeozoic 
iauuse of America, and that of the contemporaneous faunae of Europe, leaving 
to each the imprint peculiar to its continent." 
It is indeed a noble question ; and while it is one that science can settle by 
unremitting study, her votaries need not envy the triumphs of commercial 
enterprise. Let that great means of spreading good, work beneath banners of 
success, and gather in fruits tiU its barns can hold no more ; but still, there 
will be moments when labourers in the world's hive will be undazzled from the 
glare of theii* golden sun, and \vish themselves with almost a sigh of regret, 
among those few workers who are toiling in the shade, and there building up, 
with materials beyond all the gold of commerce to buy, a fabric which shall 
be a miiid-dweUing for ever ! 
