Scientific Lectures

SECOND EDITION IN these days of limited leisure, and continually increasing literary activity, when there is more and more time every intelligent man would wish to read, and apparently less and less time for reading, an apology is required for the publication of a book, however small, which does not profess to contain anything absolutely new. At the moment the very circumstances above referred to, render it desirable that, the observations of specialists should be condensed and capitonalized for the general reader, and hence the continualIy increasing demand for Iecturea which need not, because they are poplar, be the less truly scientific. The demand I have had for separate copies of my lectures may moreover excuse, if not justify, their republication. ...........