A naturalist must construct his picture of nature on the same principle that an engraver in mezzotint proceeds on his plate, beginning with the principal lights as so many different points of departure, and working outwards from each of them until the intervening spaces are covered. Some definition of an ideal scientific man might possibly be given and accepted, but who is to decide in each case whether particular individuals fall within the definition? It seems to me the best way to take the verdict of the scientific world as expressed in definite language. It may be over lenient in some cases, in others it may never have been uttered, but on the whole it appears more satisfactory than any other verdict which exists or is attainable. To have been elected a Fellow of the Royal Society since the reform in the mode of election, introduced by Mr. Justice Grove nearly thirty years ago, is a real assay of scientific merit. Owing to various reasons, many excellent men of science of mature ages, may not be Fellows, but those who bear that title cannot but be considered in some degree as entitled to the
