parts of the "Elements" which were most indispensable to a beginner. This was to
revert, to a certain extent, to the original plan of the first edition; but I
found, after omitting a great number of subjects, that the necessity of bringing
up to the day those which remained, and adverting, however briefly, to new
discoveries, made it most difficult to confine the proposed abridgment within
moderate limits. Some chapters had to be entirely recast, some additional
illustrations to be introduced, and figures of some organic remains to be
replaced by new ones from specimens more perfect than those which had been at my
command on former occasions. By these changes the work assumed a form so
different from the sixth edition of the "Elements," that I resolved to give it a
new title and call it the "Student's Elements of Geology."

In executing this task I have found it very difficult to meet the requirements
of those who are entirely ignorant of the science. It is only the adept who has
already overcome the first steps as an observer, and is familiar with many of
the technical terms, who can profit by a brief and concise manual. Beginners
wish for a short and cheap book in which they may find a full explanation of the
leading facts and principles of Geology. Their wants, I fear, somewhat resemble
those of the old woman in New England, who asked a bookseller to supply her with
"the cheapest Bible in the largest possible print."

But notwithstanding the difficulty of reconciling brevity with the copiousness
of illustration demanded by those who have not yet mastered the rudiments of the
science, I have endeavoured to abridge the work in the manner above hinted at,
so as to place it within the reach of many to whom it was before inaccessible.

CHARLES LYELL.

73 Harley Street, London,
December, 1870.