Text-Book of General Physics

Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. The class of students for which this text-book is designed is supposed to have a useful knowledge of trigonometry, but not of calculus. This is in agreement with the courses of instruction in most of our American colleges; but it has ordinarily the disadvantage of leaving rather a large inter val between the study of the philosophy of physics and the application of its principles to engineering. Especially true is this of thermodynamics and electricity where it is Often difficult for the student to recognize the fact that the un accustomed mathematical processes are simply easier means of attaining an understanding of a physical problem and not an end in themselves. For this reason the subjects men tioned are developed with somewhat more completeness than usual, so that the engineering student can find the essential notions of his advanced work logically connected with those acquired at an earlier time. Of course such an extension implies an exercise of choice on the 'part of the teacher as to what may be omitted in first reading with a class of which only a portion expects to pursue the subject farther. In Chapter XLI will be found a treatment, quite ele mentary in character, of the limiting powers of optical instruments. This is, of course, of great philosophical in terest, because it is by the means of such instruments that we attain the greatest enlargement of our intellectual horizon. Notwithstanding the simplicity of the exposition, it does-not seem to have been done before in unmathematical language.