PREFACE. XU 
which has occupied him for more than three years, 
has prevented him from quoting some authors, 
whose publications are already known to the pu- 
blic. The Chapters, for example, on the Organs 
of Perception, and the Faculties of the Mind, 
were prepared for the press several months be- 
fore the publication of the “ Physiology of the 
Mind” by the late Dr Brown. Had this not been 
the case, the author would have availed himself of 
several acute remarks of that discriminating philo- 
sopher. Should the reader detect the slightest co- 
incidence of opinion in the two publications, it can 
only be attributed to the analytical operations ha- 
ving been performed on similar subjects. Another 
work has appeared more recently, which the au- 
thor regrets was not before him in the whole 
course of his enquiries. He refers to Dr Bar- 
cLAY’s Treatise on Life and Organization. It 
should be perused with care by every student of 
Anatomy and Natural History, as an effectual pre- 
servative against the doctrines of Materialism, and 
deserves a place as well in the library of the Divine 
as in that of the Physiologist. 
In the distribution of the subjects of the follow- 
ing work, it was considered more useful to classify 
