IN preparing this work the aim has been to furnish just so much of Trigonometry as is actually taught in our best schools and colleges. Consequently, all investigations that are important only for the special student have been omitted, except the development of functions in series. The principles have been unfolded with the utmost brevity consistent with simplicity and clearness, and interesting problems have been selected with a view to awaken a real love for the study. Much time and labor have been spent in devising the simplest proofs for the propositions, and in exhibiting the best. methods of arranging the logarithmic work.

The object of the work on Surveying is to present this subject clearly and in so small a compass that students in general may find the time to acquire a competent knowledge of this important subject.

The author is under obligation to G. A. Hill, A.M., of Cambridge, Mass.; to Professor J. L. Patterson, of Chestnut Hill, Pa.; to Dr. F. N. Cole, of New York, N.Y.; to Professor S. F. Norris, of Baltimore, Md.; and to Professor B. F. Yanney, of Alliance, Ohio. Professor Yanney has done most of the work in the revision of the Surveying. Miss M. Gertrude Cross, of Boston, Mass., has furnished the drawings for this edition.