OF TRIGONOMETRY, PLANE AND SPHERICAL. ADAPTED TO THE PRESENT STATE OF ANALYSIS. TO WHICH IS ADDED, THEIR APPLICATION TO THE PRINCIPLES OF NAVIGATION AND NAUTICAL ASTRONOMY. WITH LOGARITHMIC, TRIGONOMETRICAL, AND NAUTICAL TABLES. STOR LIBRART NEW-YORK STOL FOR THE. USE OF COLLEGES AND ACADEMIES. LIBRARY BY THE REV. C. W. HACKLEY, Professor of Mathematics in the University of the City of New York. NEW YORK PUBLISHED BY WILEY & PUTNAM; COLLINS, KEÈSE & Co., NEW-YORK-THOMAS, COWPER- 1838. Entered according to Act of Congress, A. D. 1838, by Rev. C. W. HACKLEY, NEW-YORK: PRINTED BY WILLIAM OSBORN, 88 WILLIAM-STREET. PREFACE. Analytical Trigonometry has always been to the majority of college students a dry and difficult study. A conviction that it might be rendered easy and interesting to all who have a tolerable acquaintance with Algebra and Geometry, has led to the production of the present work. The faults of former treatises on this subject, which have detracted from their usefulness as books of instruction, appear to be these: 1. A too sudden transition from Geometry to Trigonometry, in consequence of which, the first efforts of the learner are in the dark as to the object of his pursuit. 2. A tedious succession of general formulæ at the commencement, the use and application of which is so long delayed as to produce weariness and discouragement before there is any apparent fruit to re ward labor. 3. Too much abridgment in the demonst and particularly in the derivation results. f |