To hear some lecturers, one would almost think that they adopted the definition of language which is reported of Talleyrand—that it was intended to conceal our ideas. Some make simple things very much otherwise by the mode of explaining them. This reminds us of a very worthy country clergyman, in the west of England, who, happening to illustrate something in his sermon by reference to the qualities of pitch, thought he should help his rustic congregation by enlarging a little on the qualities of that mineral. He accordingly commenced by saying, "Now, dear brethren, pitch is a bituminous substance:" rather a difficult beginning, we should think, to have brought to a successful conclusion. Sometimes we have heard a very unnecessary catalogue of technicalities joined with several propositions in one sentence. It is hardly to be imagined how this increases the difficulty to a beginner; whilst it impresses the excellence of that simplicity and clearness which were so charming in Abernethy. We give an example of this defect. The lecturer is describing the continuation of the cuticle over the eyes of the crustacea, as lobsters, &c.: "The epidermis (the cuticle) in the compound eyes of the crustacea passes transparent and homogeneous over the external surface of the thick layer of the prismatic corneæ, which are here, as in insects, generally hexagonal, but sometimes quadrangular; and to the internal ends of the prismatic corneæ are applied the broad bases of the hard, tapering, transparent lenses, which have their internal truncated apices directed to the retinal expansions of the numerous optic nerves." The high respect we entertain for the lecturer here alluded to, withholds us from attempting to supply a more homely version of the foregoing passage. But what an idea this must give to a student who reads it in "the outlines" of a science of which he is about to commence the study. There is nothing whatever difficult in the ideas themselves; but what a bristling _chevaux-de-frise_ of hard words, what a phalanx of propositions! We fear we should never arrive at the knowledge of many of those beautiful adaptations which all animals exemplify, if we had to approach them by such a forbidding pathway. As contrasted with simple facts thus obscured by an unnecessary complexity of expression, we may see in Abernethy how a very comprehensive proposition may be very simply expressed. Take almost the first sentence in his Surgical Lectures, the germ, as it were, of a new science: "Now I say that local disease, injury, or irritation, may affect the whole system; and conversely, that disturbance of the whole system may affect any part."