It is the great glory of Darwin to have established this firmly by an immense number of interesting and exhaustive instances, and thus placed evolution, or a scientific explanation of the development and laws of life, on a solid basis. Every day fresh discoveries and experiments confirm this great principle, and it has almost passed into the same phase as Newton’s law of gravity, as a fundamental law accepted as axiomatic by all men of science, and as the basis of modern thought, to which all religions and philosophies have to conform, accepted by nearly all modern thinkers. I may here quote a passage from an eminent Anglican divine, Dr. Temple, for the double purpose of showing how universal has become the acceptance of this Darwinian view of evolution among intelligent men; and how little terrible are its consequences, even to those who look at the facts of the universe through a theological medium and retain their belief in accepted creeds. ‘It seems in itself something more majestic, more befitting of Him to whom a thousand years are as one day, and one day as a thousand years, thus to impress His will once for all on this creation, and provide for all its countless varieties by this one original impress, than by special acts of creation to be perpetually modifying what He had previously made.’[1] [1] Dr. Temple, _Religion and Science_. Scientific men would be content to accept this statement of Dr. Temple’s almost in his own words, except that they might consider his definition of the Great First Cause as somewhat too absolute and confident. Having had to deal so much with actual facts and accurate knowledge, they are apt to be more modest in assertion than even the most enlightened theologian, whose studies have lain rather in the direction of phrases and ideas, which, from their very nature, are more vague and indefinite, and perhaps rather guesses and aspirations after truth, than proofs of it. In any case there is the authority of a learned and liberal-minded bishop for the position that the scientific way of looking at the universe is not necessarily profane or irreligious. To return to variation: the instances of the operation of this principle, alone or in conjunction with that of heredity, in working out the evolution of species, are exceedingly numerous and interesting. Those who wish to understand the subject thoroughly must study the works of Darwin, Haeckel, Huxley, and other modern writers; but for my present purpose it will be sufficient to refer to a few of the most marked instances which may assist the reader in comprehending how the gradual evolution of life and creation of new species may have been brought about.