ELEMENTS OF DESCRIPTIVE 

 GEOMETRY 



By CHARLES E. FERRIS, Professor of Mechanical 

 Engineering, University of Tennessee 



THE leading engineers and draughtsmen, as investigation 

 shows, do nearly all their work in the third quadrant or 

 angle. It seems reasonable, therefore, that the subject 

 of descriptive geometry should be taught in technical and 

 scientific schools as it will be used by their graduates. 

 ^[ Many years of experience in teaching descriptive geometry 

 have proved to the author that the student can learn to think 

 with his problem below the horizontal, and behind the vertical 

 and perpendicular planes, as well as above and in front of 

 those planes. 



^[ This volume forms an admirable presentation of the subject, 

 treating of definitions and first principles ; problems on the 

 point, line, and plane ; single curved surfaces ; double curved 

 surfaces ; intersection of single and double curved surfaces by 

 planes, and the development of surfaces ; intersection of solids ; 

 warped surfaces ; shades and shadows ; and perspective. 

 ^[ Besides dealing with all its problems in the third angle 

 instead of in the first, the book presents for each problem a 

 typical problem with its typical solution, and then gives 

 numerous examples, both to show variations in the data, and to 

 secure adaptability in the student. In consequence, no sup- 

 plementary book is necessary. 



^| To show the projections on the horizontal, and on the 

 vertical planes, it uses v and h as exponents or subscripts 

 instead of the usual method of prime, etc. 

 ^[ In scope the treatment is sufficiently broad, and yet it is 

 not so abstruse as to make the book difficult for the average 

 college course. Both text and plates are bound together, thus 

 being very convenient for use. There are 113 figures. 



AMERICAN BOOK COMPANY 



