years ago), its production, form, colour, is worthy of the intellect of the most profound philosopher, while it is an unfailing source of amusement and instruction to the youthful mind.
But, my young friends,—and it is to you I shall address myself in these lectures, although I am glad to see so many present who are older in years, but who can still relish a simple lecture to juveniles,—there is another department of nature that is not, strictly speaking, the province of the natural philosopher. There are the phenomena of living matter, the events that happen in the life-history of living beings, the changes that occur in our own bodies, and on which our lives depend. These are investigated by the physiologist; and we shall find, as we go on, that they are not so easily demonstrated as many of the phenomena that happen in dead matter, and that they are, on the whole, more difficult to understand. Following, however, the example of previous lecturers, I have endeavoured to choose a subject, the consideration of which will form an introduction to physiology, which will illustrate how physiologists work in their laboratories, and how
