intelligible style, but, as it was composed while the doctor was absorbed in his investigations, it is somewhat defective in classification and condensation. This is to be regretted, yet it is quite a secondary matter. Mr. Wallace deprecates its literary defects, but cordially concedes its scientific importance. He says: "It is so full of curious and novel facts and experiments, it contains so much excellent reasoning and acute criticism, and it opens up such new and astounding views of the nature and origin of life, that one feels it ought to and might have ranked with such standard works as the 'Origin of Species' and the 'Principles of Biology,' if equal care had been bestowed upon it as a literary composition."
IT may have occurred (and very naturally, too, to such as have had the curiosity to read the title of this lecture) that it must necessarily be a very dry and difficult subject; interesting to very few, intelligible to still fewer, and, above all, utterly incapable of adequate treatment within the limits of a discourse like this. It is quite true that a complete setting forth of my subject would require a comprehensive treatise on logic, with incidental discussion of the main questions of metaphysics; that it would deal with ideas demanding close study for their apprehension, and investigations requiring a peculiar taste to relish them. It is not my intention now to present you with such a treatise.
The British Association, like the world in general, contains three classes of persons. In the first place, it contains scientific thinkers; that is to say, persons whose thoughts have very frequently the characters which I shall presently describe. Secondly, it contains persons who are engaged in work upon what are called scientific subjects, but who in general do not, and are not expected to, think about these subjects in a scientific manner. Lastly, it contains persons who suppose that their work and their thoughts are unscientific, but who would like to know something about the business of the other two classes aforesaid. Now, to any one who, belonging to one of these classes, considers either of the other two, it will be apparent that there is a certain gulf between him and them; that he does not quite understand them, nor they him; and that an opportunity for sympathy and com-
- A Lecture delivered before the members of the British Association, at Brighton, August 19, 1872.