Image from the Biodiversity Heritage Library.
Contributed by Harvard University Botany Libraries.
| www.biodiversitylibrary.org
Transcription
1. Hold box in palm of hand and level with
the universal bubble.
2. Turn front sight half up.
3. Adjust lid until object can be seen
in the mirror.
4. The sights are probably crossed - move
head to one side or the other until
sights are parallel.
5. Swing the body until the sights
are on the object.
6. Read!