This phototheodolite was made by J Hicks. The Bridges-Lee phototheodolite comprised a camera set on the horizontal plate of a theodolite, with a telescope and vertical arc set on top of the camera. Horizontal and vertical lines appeared on the negative, along with the direction of the magnetic meridian and the orientation of the camera. Many surveys of open mountainous territory such as Canada and Switzerland were made with this type of apparatus.
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