Hilger Watts Theodolite Manual 95%

Note: Hilger & Watts produced several theodolite models (e.g., TM 1A, TM 6, 20-second, 1-second). The following is a general guide applicable to their classic 6-inch (150mm) glass circle theodolites, which are the most common in collections and field use today.

Born from the 1948 merger of E.R. Watts & Son and Adam Hilger Ltd., this instrument carried the weight of London’s finest optical engineering. The manual was a sacred text, often found tucked into the lid of a fitted steel case, smelling of machine oil and old paper. It didn't just tell you how to measure; it taught you how to see. 2. The Ritual of Setup hilger watts theodolite manual

18;write_to_target_document7;default18;write_to_target_document1a;_FP_tafvaEqmKwbkPwtSNsAU_20;a5; 0;1e37;0;4c53; Note: Hilger & Watts produced several theodolite models (e

4. Adjustments & Calibration (From the Manual)

Periodic checks (every 3-6 months):

B. Centering (Optical Plummet)

• Look through the optical plummet eyepiece (located near the base).
• Adjust focus ring.
• Loosen the tribrach clamp and slide the instrument until the ground point is exactly at the crosshair center. Re-tighten.

A standard Hilger & Watts manual breaks the instrument down into several critical systems: The Levelling Base (Tribrach) Look through the optical plummet eyepiece (located near

Step 3: Rough Centering & Leveling

1. Look through the Optical Plummet (or down the hollow axis).
2. Use the footscrews to center the crosshair over the ground point.
3. Adjust the tripod leg lengths until the Circular Bubble is roughly centered.

1. Leveling: Ensure the tripod is stable and level. Use the leveling screws to level the instrument.
2. Centering: Center the instrument over the survey point using the centering pin or plumb bob.
3. Orientation: Orient the instrument to a known reference point.