The amateur's perspective : being an attempt to present the theory in the simplest form; and so to methodize and arrange the subject, as to render the practice familiarly intelligible to the uninitiated in a few hours of study (1828)
Davenport, Richard, author · London : Printed for the author · leaf 28
be a right line parallel to the same. But the objects in the 2nd diagram (No. 9), are further distant from the base than those of No. 8. The perspectives of those lines then, will be shorter than that of the former, as proved by those diagrams, and higher , as proved in Sect. V. diag. 3. The ground… … And the lines in No. 1 1 will be the perspectives of lines on the ground plane, parallel to the plane and base ofi the picture. Section XIII. It remains to find the perspective of lines on the ground plane, perpen- dicular to the plane of the picture. (See note to Sect. IX.) To recur to our window…
Perspective
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.