chapter on Light, in particular, many drawings are called for, since the making of diagrams affords an interesting and exact method of examining the principles of optics. The student should be required to use compasses and ruler so carefully that his drawings will amount to demonstrations. A separate chapter is given to simple applications of the graphic method.
Without encroaching in the least on the field of the text-book or the laboratory manual, to which this collection is merely auxiliary, it has seemed best to prefix to certain of the problems an occasional formula, definition, or explanation. These are intended merely to suggest the character and range of the problems or to give some hint of the principles involved. The whole has been subjected to the test of the classroom.
THE HOTCHKISS SCHOOL, LAKEVILLE, CONN.,