| 356 / | HD | OPTICS: MEASURING AND TESTING |
| 138 | DF | ANGLE MEASURING OR ANGULAR AXIAL ALIGNMENT {11} |
| 140 | DF | .~ Apex of angle at observing or detecting station {6} |
| 142 | DF | .~.~ Scale and remote point simultaneously observable {1} |
| 143 | ![]() | .~.~.~ Artificial reference |