Comprehensive manuals for vintage Hilger & Watts theodolites, manufactured from the 1930s to the 1960s, are available through specialized archives and digital repositories. Key resources include the Vintage Machinery Archive
Actionable routine: For field checks each morning, perform a three-peg test or equivalent angular repetition to quantify combined instrument and setup error.
- Plate level calibration (reversal test)
- Collimation adjustment (horizontal line of sight)
- Vertical index error (index bubble or correction)
- Optical plummet centering
- Reticle rotation (vertical crosshair alignment)
3. Standard Operating Procedure (Derived from Original Manual)
A. Setting Up
- Tripod: Extend legs to chest height; press firmly into ground.
- Attach Theodolite: Screw tribrach onto tripod head.
- Coarse Leveling: Adjust tripod legs so the circular bubble is roughly centered.
- Fine Leveling: Use the three foot screws to center the plate level bubble (long, sensitive bubble). Rotate instrument 90° and repeat.
. It teaches the operator how to physically interact with the micrometers and tangent screws to achieve sub-second accuracy. Value for Collectors
The most famous models include the Microptic Theodolite (Models T0, T1, T2, T3) and the Watson "M" Series. Each model requires a specific Hilger Watts theodolite manual due to differences in their clamping systems, bubble levels, and micrometer optics.