Hilger Watts Theodolite Manual

Use the legs of the tripod to place the optical plummet roughly over the ground point.

Their theodolites were distinct for several reasons:

Plunge the telescope (rotate it vertically 180 degrees) and rotate the body 180 degrees to place the instrument in . Sight the exact same target again and record the readings. The Check: The horizontal readings should differ by exactly . The sum of the vertical readings should equal exactly hilger watts theodolite manual

To measure a : Sight the first target (e.g., Point A), record the horizontal angle. Swing the telescope to the second target (Point B) and record the new angle. The difference is your horizontal angle.

[ Objective Lens ] | [ Telescope Barrel ] --- (Focusing Ring) | (Vertical Clamp) --- [ Standards ] --- (Optical Reading Eyepiece) | [ Horizontal Clamp ] | [ Tribrach Base ] | (Footscrews x3) Use the legs of the tripod to place

| Model/Family | Key Features and Use Cases | Likely Manual/Catalogue | | :--- | :--- | :--- | | | The iconic, compact transit theodolite from the 1950s-60s . Weighed just 9 lbs, significantly lighter than its predecessors, making it highly portable for general surveying. Its design allowed the telescope to swivel completely, a "transit" feature for taking both fore and back sights. | CS30: Watts microptic theodolite no. 1: Instructions for use CS16/4: Microptic Theodolite No. 1 CS16/5: Watts microptic theodolite no. 1 Mark IV | | Microptic Theodolite No. 2 | A more advanced model providing higher precision, likely with a larger circle for finer readings. Often used for more demanding engineering projects. | CS15: Watts microptic theodolite no. 2 CS15/7: Microptic Theodolite No. 2 | | Microptic Theodolite No. 3 | A high-precision instrument capable of direct readings to 1/5th of a second of arc. Suitable for geodetic surveys and other highly precise applications. | Likely found in later catalogues, possibly CS 100 series. | | Watts Vernier Theodolites | Traditional design using vernier scales to read the circles. Slightly older technology than microptic models, but robust and reliable. | CS100/1: Watts general catalogue of survey equipment, Section 1: Vernier & Micrometer Theodolites CS100/2: Watts vernier theodolites | | Mining Theodolite | A specialized robust theodolite designed for underground use, often with features like illumination for reading circles in dark conditions. | Included in the CS100/1 catalogue. | | Rangefinder-Theodolite | Combined functions of a theodolite and a rangefinder, allowing for simultaneous angle and distance measurement. | Likely listed as catalogue numbers ST 36, SD 1-2 . |

[ Telescope Focus Ring ] | [ Eyepiece Focus ] ------ [ Optical Sight ] | [ Vertical Circle Housing ] | [ Circle Reading Eyepiece ] | [ Upper Tangent Screw ] --- [ Plate Bubble Level ] | [ Lower Tangent Screw ] | [ Tribrach Base ] | [ Levelling Footscrews ] The Check: The horizontal readings should differ by exactly

A step-by-step guide is given in the 1986 training film: "Setting up a theodolite -- Measuring horizontal angles -- Measuring vertical angles -- Packing up".

: Angles are viewed through a secondary eyepiece located next to the main telescope. Use the micrometer or coincidence knob

By the late 1940s, Hilger & Watts had grown to employ around 1,300 people across six factories in southeast England. The company became particularly famous for its , which were notably more compact and lighter than earlier designs, weighing as little as 9 lbs (approx. 4 kg). In 1969, the company was acquired by the Rank Organisation, eventually leading to the sale of its surveying equipment business in 1979.