214 JOURNAL OF THE PLYMOUTH INSTITUTION. 
introducing some new element, or more fully developing what 
already existed. According to this theory the chain of animate 
life was a mere mechanical thing, every link having been forged by 
a distinct act of the Creator's will. According to the evolutionist, 
each link was an organic " part of one stupendous whole, whose 
body Nature is, and God the soul." Each later link had grown out 
from an earlier one, and implied a necessary predecessor. Both 
dogmas were hypothetical, but in a different sense. The dogma of 
Creationism was a mere hypothesis, whose assumptions were in 
conflict with biological and geological facts. Indeed, the theory of 
evolution owed its inception in a large measure to the observed 
insufficiency of the hypothesis it replaced. Darwinism, unlike its 
rival, was suggested by observation, accorded with fact, and had in 
at least one splendid instance been verified. The evolution theory 
originated in observations made by Mr. Darwin during the scien- 
tific expedition sent out in the Beagle, relative to the geographical 
distribution of animals, which seemed to throw some light on the 
origin of species. On his return he began to accumulate facts and 
make experiments, and in 1859 he felt himself justified in putting- 
forward the hypothesis " that existing forms of life are descendants 
by true generation of pre-existing forms." The world of animal 
life shows us the operation of two great laws — the law of inheri- 
tance, and the law of variation. Controversy began with the 
question, Would these laws explain the origin not only of varieties, 
but of species % Darwinism answered the question in the affirma- 
tive. An example, quoted from Mr. Darwin's works, was the 
multitudinous varieties of the tame pigeon, many of which the 
ornithologist w r ould classify as separate species if they were shown 
him as wild birds. What man had done in a few instances and in 
a few years, Darwin believed that Nature, working through im- 
measurable ages, and amid frequently and widely varying conditions, 
had done in many instances. The means by which such stupendous 
changes had been brought about Darwin formulated and named as 
natural and sexual selection. To the argument that the time required 
for the effects attributed to evolution was immensely greater than 
physical philosophy would place at our disposal, and the conflict 
between Sir William Thompson and Professor Huxley as to the 
period for which the earth had been fitted to be the abode of 
animal life — he said, they were sure of their facts; and when the 
geologist and the physicist had fought out their battle, and not 
