GENERAL MEETING. 7 
On the question whether geology itself gave us “traces of a begin- 
ning, or prospects of an end,” Mr. T. argued that stratigraphical 
geology unmistakably indicated its own genesis in the plutonic char- 
acter of its primeval “Archean,? or Laurentian—pointing to a 
time when the primitive surface was a molten ocean; and that 
when read in the light of palzontology such indication of a begin- 
ning was strengthened into convincing proof. by the receding grada- 
tions of animal and vegetable life, starting in the lower Silurian 
and its underlying Cambrian, with the humblest invertebrate forms 
of molluscan and crustacean life, and the simplest cryptogamous 
thallogens—the marine algze and fucaceze. And in this connection 
he referred to the memorable generalization of Louis Agassiz—that 
the geological successions of animal types correspond remarkably 
with the phases of embryonic development—as one of the most sug- 
gestive contributions ever made to the theory of evolution. 
The speaker then turned to the question of the earth’s interior 
fluidity; and after stating that the celebrated mathematical argu- 
ments of Hopkins from the “precession” value, and of Thomson 
from the hydrographic tides, had both been practically abandoned 
by the latter—though he still persisted in his pre-possessions for a 
solid globe (mainly on the specific-gravity skepticism), Mr. T. said 
he felt no difficulty whatever in accepting the geological evidences of 
a fluid earth enveloped by a flexile, friable egg-shell. With regard 
to the large amount of contraction and corrugation every where 
exhibited by this shell, he admitted that Mr. O. Fisher had conclu- 
sively disproved the sufficiency of Elie de Beaumont’s plausible 
hypothesis that the contraction is due to the secular cooling of the. 
planet. Mr. Fisher had however no better speculation to offer; 
and the answer to the riddle must come ultimately—not from petrol- 
ogy; nor from structural, or stratigraphical, or physiographical 
geology—but from cosmological physics. In conclusion, the speaker 
urged that the same inductions which so clearly establish the birth, 
the childhood, and the manhood of our planet, as inevitably impli- 
cate its decline, decadence, and decease; and he quoted passages 
from Byron’s familiar lines on “ Darkness,” as in the main a scien- 
tific prophecy. 
Mr. Paut spoke of the importance of a recent contribution to the 
subject of the earth’s rigidity by Mr. George H. Darwin. Mr. Gix- 
BERT thought that Darwin’s deduction of high rigidity was vitiated 
by his postulate of homogeneity. 
