PREFACE. 
Vll 
which he considers a far more important purpose of the study, 
—namely, the culture and discipline of the Mind itself Having 
been satisfied, by no inconsiderable experience of different 
modes of Education, that Natural Science, if judiciously 
taught, is second in value to no other subject as an educational 
means , and that it may be made to call forth a more varied 
and wholesome exercise of the mental powers than almost any 
other taken singly,—he has kept this purpose constantly in 
view; and he trusts that the experience of intelligent In¬ 
structors will be found so far to concur with his own, that the 
study of Physiology may be still more generally introduced 
into Popular Education. It can only be by the general diffu¬ 
sion of sound information on this subject, that the Public 
Mind can be led to understand the difference between 
Rational Medicine, and that Empiricism which now presents 
itself under so many different forms ; that it can appreciate 
the true value of measures of Sanitary Reform, the efficiency 
of which must depend upon the amount of support they 
receive from an intelligent public opinion; and that it can 
be preserved from those Epidemic Delusions, whose preva¬ 
lence, from time to time, is not less injurious to the minds 
of which they lay hold, than is that of Epidemic Diseases to 
the bodies of those who suffer from them. 
He has only further to add that, whilst keeping in view 
the most important practical applications of the Science of 
Physiology, he has not thought it desirable to pursue these 
too far; since they constitute the details of the Art of pre¬ 
serving Health, which is founded upon it, and which may be 
much better studied in a distinct form, when this outline of 
the Science has been mastered. And, for the same reason, 
he has adverted but slightly to those inferences respecting the 
Infinite Power, Wisdom, and Goodness, of the Great Eirst 
Cause, which are more obvious, although, perhaps, not really 
more clear and valid, in this Science, than in any other. 
