724 
INTRODUCTORY LECTUK KS. 
to the time he has employed in diligent labour. The experienced 
eye — the power of perceiving the minute differences which dis- 
criminate or unite the objects placed before us — the readiness of 
comparing new phenomena with those that are already treasured 
up in the snind, these are accomplishments which no rules can 
teach, and no precepts can put us in possession of. It is a por- 
tion of knowledge which every one must acquire for himself, and 
which no one can leave as an inheritance to his successor. We 
cannot, therefore, begin too early, or see too much. By habitual 
exercise our senses will acquire a delicacy truly astonishing, and 
it is to this that we trace the marvellous sagacity with which 
some skilful observer seizes the phenomena which entirely escape 
the attention of others. What is that which prevails so often 
over the greatest erudition, and the most solid information, but 
the frequent, and methodical, and just exercise of the senses. 
It is that tact for which some observers are so remarkable, and 
which all might possess by the exercise of sufficient labour and 
diligence. 
“ The too prevailing fault of the pupil is, that he neglects the 
hospital practice. The materials of observation, to a greater or 
less degree, are always to be found there. There is a variety of 
disease to be studied with little expenditure of time — there phe- 
nomena may be most closely scrutinized, the treatment of the 
patients is completely under control, and the effect of remedies 
there most clearly demonstrated ; and when death takes place, 
the diagnosis of the practitioner can be put to its ultimate test, 
and the effects of disease on the structures of the body can be 
studied with the best aids, and on the largest scale. 
“The great use of clinical lectures is, to prepare us to under- 
stand and to appreciate the phenomena of disease when pointed 
out by those whose time and attention have been especially di- 
rected to these observations and study. With the advantage of 
an experienced guide, we not only learn much more in the same 
time, but we observe many things that would otherwise pass un- 
noticed before our eyes. Many appearances of great practical 
importance will be demonstrated, which the student had seen 
almost daily, but which now, for the first time, arrest his attention. 
It is only by following the visits of skilful practitioners that they 
who are entering on their career can rapidly acquire experience. 
Young men are too apt to pride themselves on their skill and 
sagacity; but they may depend upon it, that medicine can be 
learned only with a medical man and with patients. They can- 
not form themselves without aid. They must have a practised 
guide, or they will wander in the mazes of error, or sink into em- 
piricism. Bo not suffer yourselves to be deceived by the belief 
