This edition of Dr. DE BOER'S recent work is produced in the hope that it may prove interesting to not a few English readers, and especially that it may be of service to younger students commencing to study the subject which is dealt with in the following pages. The translator has aimed at nothing more than a faithful reproduction of the original. His best thanks are due to the accomplished author, for his kindness in revising the proof-sheets of the version, as it passed through the Press.
E.R.J.