you omit this they will be feeble and barren in their results. When you read or are told that an artery pulsates, that it is composed of so many coats, each possessing peculiar properties and uses, you will see and feel the artery to beat, you will examine its coats, you will see their properties exemplified in life, in death, in health, and in disease: in health, when it is divided by the knife, or tied to arrest hæmorrhage; in disease, when it is the seat of aneurism and other changes. Of what service would it be to you to read of all this? You would be better almost without such miserably insufficient information. Besides, what you read may not be true; you will decide for yourselves whether it is or not. If you wish to see the result of an education which makes a man arrive at an opinion accurately, act boldly, display manual dexterity, and effect good results, you may see it in any of the surgeons while deligating an artery to cure an aneurism. Again, supposing you to have made yourselves acquainted with the most complete account of typhoid fever, and simply to have supplemented what you have so learned by looking at any number of cases, and hearing what others have to say upon them. Until you have tested for yourselves the truth of all that you have heard or read about the disease, your knowledge would be worse than useless, for you might fancy that you know something about it, and, armed with such conceit, have the effrontery to take charge of a patient so suffering. When you have seen patients every day from the beginning to the end of the fever, have taken the temperature of their bodies and noted its variations, become so familiar with their pulses that you recognize the period at which it may be necessary to administer stimulants, examined the excretions, watched the changes in symptoms, noted the effects of treatment, observed every detail in diet and nursing, made yourselves acquainted with the affections which the fever leaves behind, witnessed the modes of death with patients who do not recover, examined the post-mortem changes in those who die from it, and, lastly (most important of all) have discovered the source whence the fever arose—if you have done all these things, your knowledge of the subject will be real, and you will have learned that, though books have their uses, they should in science and medicine be only used for the purpose of directing attention to what is to be looked for, and as a means of comparing the observations of others with your own. Thus far, then, books may be relied upon and no further. If this be so, the very essence and goodness of a scientific education is lost when a student endeavors to pass his examinations by learning from text-books what he should have taught himself by observation, and from pictures what he should have learned from realities. Those whose information is so gained have seized the shadow instead of the substance, and their work will for ever bear the marks of their indifferent education.
The results of the two modes of acquiring knowledge will be seen in the different classes of practitioners which they respectively pro-
