Hilger Watts Theodolite Manual -

This is the most unique part of Hilger & Watts instruments. The manual describes a coincidence method:

Example: Circle shows 45°; micrometer reads 12' 30" → 45° 12' 30". hilger watts theodolite manual

Locate the small rotating eyepiece (usually near the telescope eyepiece or on the side of the instrument). This focuses the internal scale. This is the most unique part of Hilger & Watts instruments

Following these steps precisely—exactly as written in the Hilger Watts theodolite manual—can restore an instrument from being a paperweight to being accurate to within a few arc-seconds. Example: Circle shows 45°; micrometer reads 12' 30"