PresidenVs Add^^ess. 
195 
wider field of foreign geology ; ever remembering that what 
is limited and irregular in one district may be continuous 
and regular in another, and that we are bound always to 
take the fullest development we can discover as the typical 
standard of our groups and systems. Let us then abide by 
this idea of passage beds as a provisional convenience, avoid- 
ing all sharp demarcations between contiguous systems, be- 
lieving that nature's operations are incessant and continuous, 
and that all breaks, whether physical or vital, are at the 
most but local and limited phenomena, 
6y sternal Arrangements, — A fourth point to which we 
would direct attention is the discovery of numerous second- 
ary coal-fields, and the effects of such discoveries, Jirst, on 
many cherished theories respecting the conditions of the Car- 
boniferous era ; and, second, on the chronological arrangement 
of our secondary formation. The fact that we have import- 
ant coal-fields of triassic, oolitic, and cretaceous life, like 
those of Virginia, Brazil, Vancouver's Island, Austria, India, 
the Indian Archipelago, and Australia, must for ever set 
aside as untenable all hypotheses of abnormal climates, car- 
bonic acid atmospheres, and universal conditions for the 
carboniferous epoch. The fact is, that coal is a product of 
every age, and that the coal-forming conditions, like other 
conditions, will vary in intensity according to the geogra- 
phical arrangement of sea and land, and the consequent 
climatic influences which such arrangements may induce. 
Besides, we are far from having proved the strict contem- 
poraneity of the so-called Palaeozoic coal-fields ; on the con- 
trary, every new foreign survey raises the gravest doubts on 
this point, and leads to the belief that these old coal-deposits 
range throughout the whole cycle embraced by the Devonian, 
the Carboniferous, and Permian systems of the British Islands. 
Again, the difiiculty which foreign surveyors find in co-ordi- 
nating their discoveries with our trias, lias, oolite, and chalk, 
suggests the idea that the time is not far distant when we 
must modify the range and nomenclature of these arrange- 
ments. Be it from America, India, Australia, or New Zea- 
land, complaints are continually reaching us of the difficulty, 
or even impossibility, of co-ordinating their strata with those 
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