THE PRESENT CONDITION OF ORGANIC NATURE.

When it was my duty to consider what subject I would select for the

six lectures* ([Footnote] *To Working Men, at the Museum of Practical

Geology, 1863.) which I shall now have the pleasure of delivering to

you, it occurred to me that I could not do better than endeavour to put

before you in a true light, or in what I might perhaps with more modesty

call, that which I conceive myself to be the true light, the position

of a book which has been more praised and more abused, perhaps, than any

book which has appeared for some years;--I mean Mr. Darwin's work on the

"Origin of Species". That work, I doubt not, many of you have read; for

I know the inquiring spirit which is rife among you. At any rate, all

of you will have heard of it,--some by one kind of report and some by

another kind of report; the attention of all and the curiosity of all

have been probably more or less excited on the subject of that work. All

I can do, and all I shall attempt to do, is to put before you that kind

of judgment which has been formed by a man, who, of course, is liable

to judge erroneously; but, at any rate, of one whose business and

profession it is to form judgments upon questions of this nature.

And here, as it will always happen when dealing with an extensive

subject, the greater part of my course--if, indeed, so small a number of

lectures can be properly called a course--must be devoted to preliminary

matters, or rather to a statement of those facts and of those principles

which the work itself dwells upon, and brings more or less directly

before us. I have no right to suppose that all or any of you

are naturalists; and even if you were, the misconceptions and

misunderstandings prevalent even among naturalists on these matters

would make it desirable that I should take the course I now propose to

take,--that I should start from the beginning,--that I should endeavour

to point out what is the existing state of the organic world,--that I

should point out its past condition,--that I should state what is the

precise nature of the undertaking which Mr. Darwin has taken in hand;

that I should endeavour to show you what are the only methods by which

that undertaking can be brought to an issue, and to point out to you how

far the author of the work in question has satisfied those conditions,

how far he has not satisfied them, how far they are satisfiable by man,

and how far they are not satisfiable by man.

To-night, in taking up the first part of this question, I shall

endeavour to put before you a sort of broad notion of our knowledge of

the condition of the living world. There are many ways of doing this. I

might deal with it pictorially and graphically. Following the example of

Humboldt in his "Aspects of Nature", I might endeavour to point out the

infinite variety of organic life in every mode of its existence, with

reference to the variations of climate and the like; and such an attempt

would be fraught with interest to us all; but considering the subject

before us, such a course would not be that best calculated to assist us.

In an argument of this kind we must go further and dig deeper into the

matter; we must endeavour to look into the foundations of living Nature,

if I may so say, and discover the principles involved in some of her

most secret operations. I propose, therefore, in the first place, to

take some ordinary animal with which you are all familiar, and, by

easily comprehensible and obvious examples drawn from it, to show what

are the kind of problems which living beings in general lay before us;

and I shall then show you that the same problems are laid open to us by

all kinds of living beings. But first, let me say in what sense I have

used the words "organic nature." In speaking of the causes which lead

to our present knowledge of organic nature, I have used it almost as an

equivalent of the word "living," and for this reason,--that in almost

all living beings you can distinguish several distinct portions set

apart to do particular things and work in a particular way. These are

termed "organs," and the whole together is called "organic." And as it

is universally characteristic of them, this term "organic" has been very

conveniently employed to denote the whole of living nature,--the whole

of the plant world, and the whole of the animal world.

Few animals can be more familiar to you than that whose skeleton is

shown on our diagram. You need not bother yourselves with this "Equus

caballus" written under it; that is only the Latin name of it, and does

not make it any better. It simply means the common Horse. Suppose we

wish to understand all about the Horse. Our first object must be to

study the structure of the animal. The whole of his body is inclosed

within a hide, a skin covered with hair; and if that hide or skin be

taken off, we find a great mass of flesh, or what is technically called

muscle, being the substance which by its power of contraction enables

the animal to move. These muscles move the hard parts one upon the

other, and so give that strength and power of motion which renders the

Horse so useful to us in the performance of those services in which we

employ him.

And then, on separating and removing the whole of this skin and flesh,

you have a great series of bones, hard structures, bound together with

ligaments, and forming the skeleton which is represented here.

(FIGURE 1. Section through a horse.

Lectures and Essays(#6414) · 第 28 / 56 题