To facilitate the acquisition of the leading principles ought to be the first object of an elementary book, and most of all ought we to study simplicity in a work treating of Anatomy. When the way is smoothed, the student feels a rapid progress, and is pleased with his own exertions; and it requires only a little self-examination to be assured that much of our partiality for any particular line or object of study, often results from a real or fancied superiority of knowledge; perhaps in Anatomy, more than in any other pursuit, it is necessary to make the student sensible of his progress, before he can feel any thing like enthusiasm, or even partiality for it.

It is upon the simplicity of these Plates, therefore, more than upon their elegance, or their accuracy, (though I am confident that in this last respect they are not deficient,) that I would place their merit. When the importance of the study of the Arteries is considered—a point so fully enforced and illustrated in the volume of the text to which I mean these plates to be attached—this book must, I think, be an acquisition to the student, since I am conscious that I should myself have found it to be so in the commencement of my studies; it is with this feeling that I offer it with confidence to the public. I am assured, also, that the study of the Blood-vessels and Nerves from Plates, prepares us better for undertaking any surgical operation than that of bare description, however accurate, however simple, or however constantly the true practical inferences may be kept in view. It is upon the eye that the impression must be made, which is to enable us, in looking upon a limb, to mark the course of the Arteries: Drawings are a kind of notes, too, more easily consulted; and bring to the mind, in a more lively manner, all that was associated in our first studies.

In following the course of the Arteries we must have continual occasion to observe, that if one branch deviate from the more general course, or be of an unusual size, the neighbouring branches have also an unusual form. In the arteries of the arm, for example, were we to observe the great Thoracic Artery of an uncommon size, and sending large branches under the Latissi-mus Dorsi, and under the Scapula; were we to take our drawings of this Artery as an example of a beautiful distribution of the external Mammary Artery, without attending to the effect of such distribution on the Subscapular Artery; or again, were we to draw the Subscapular Artery of the great comparative size which it not unfrequently takes; we should not give a just representation of the natural and most usual distribution of those Arteries: for, as we find that the distribution of the Thoracic Arteries materially affects the distribution of the Articular Arteries and of the Profunda, although it be absolutely necessary in the text to describe the size and importance of this Artery, because in our operations at this part we must keep in view the more dangerous and unfavourable circumstances, it does not follow that we are to make our drawings by the same rule; we should by doing so make them monstrous and unnatural.

We thus see the necessity of combining drawing with description. In the latter we mark all the variety of distribution, and the peculiarities of each branch considered individually; but this again naturally produces intricacy, unless, by comparison with the drawings, and their short explanations, we can take a rapid and general view of the course of the vessels. The drawings ought, therefore, to give the representation of the more general distribution, while the varieties and peculiar forms are left to description. And here comes a question of some consequence—How is a selection from the great variety of distribution of the vessels and nerves of the body to be made?

I am very averse from the ideas most prevalent regarding Anatomical Tables, that it is impossible to make a true representation of the parts from any individual body; for, as we see, in looking over the variety of Anatomical Tables, that those which have the characters of the parts distinctly marked, and have been evidently drawn from the parts dissected and laid out before the artist, are in greatest esteem for the accuracy of the anatomy, and best bear the only true test of excellence, the immediate comparison with the subject in the dissecting room; so, on the other hand, those made by first drawing the outlines of the parts, and then the vessels, are plans merely, in which the character of the parts, and the peculiar course and turnings of the vessels, are lost.

But I hope I shall not be understood to say, that if a drawing be made accurately from the subject, it will therefore answer all the purposes required. Of twenty bodies, not one, perhaps, will be found fit for drawing; but still I conceive that we are not to work out a drawing by piecing and adding from notes and preparations; we are to select carefully from a variety of bodies, that which gives largeness of parts, where the characters of parts are well marked, and where there is the most natural and usual distribution of vessels. In making our drawings of such dissections, let us allow ourselves no license, but copy accurately. By noting in the description any little deviation, every necessary end is answered.

By long attention to the subject, I hope that I have been able to make these Plates simple, intelligible, and accurate. While the design of this book of Plates is to present to the student, at one glance, the general distribution of the vessels, and to fix them in his memory in a way which no description can accomplish, it will be found to give the most usual distribution of the branches; for I have been careful in the selection of my subjects.

In studying the Arteries, or any part of Anatomy, we should, in the first place, run the eye over the corresponding plate, then read the general description in the text; and lastly, proceed to study more closely, step by step.

I know the difficulties which the student must encounter in acquiring a comprehensive knowledge of the nerves; the books on that subject being more confused and intricate to study, than the most irregular dissection. The next part, therefore, of this work, comprehends the Nervous System, though the present book I conceive to be complete in itself.