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THE PLATES
NOTE AS TO THE REFERENCE LETTERS
While ordinary Latin capitals and minuscules were selected as being the more suitable for the diagrams, owing to their upright character, yet the corresponding small italic letters have been employed in the text because of their greater conspicuousness. In case this should cause inconvenience to any reader of other than English nationality, who is not quite familiar with both these forms of small letters, the following list of the two sets of equivalent characters may be found useful:—
| Letters in Diagrams | Equivalent in Text | Letters in Diagrams | Equivalent in Text |
| a b c d e f g h i j k l m |
a b c d e f g h i j k l m |
n o p q r s t u v w x y z |
n o p q r s t u v w x y z |
LIST OF PLATES
| PLATE I | ||
| NO. OF DIAGRAMS | BETWEEN PAGES | |
| Figs. 1 to 4h. | Conjugate Focal Distances for Plane and Spherical Reflecting and Refracting Surfaces | 6 and 7 |
| PLATE II | ||
| Figs. 4g to 7b. | Conjugate Focal Distances for Second Surfaces and Lenses | 10 and 11 |
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