The photographs Mrs. Johnston purchased (as above and here) were often superior to reproductions in art books of the time (below).

From these lecture notes, we see how Mrs. Johnston took a rather poor image - like the Velazques in the contemporary art history text, above- and brought it to life. Her discussion of another Velazques painting starts at the arrow, below.

1st image from photograph courtesy of Oberlin College Still Library

2nd image from A History of Art for Beginners and Students... by Clara Erskinde Clements. New York, Frederick A. Stokes, 1887

3rd image from photocopy; original Oberlin College Archives