Gerlach repetitive compass theodolite

The theodolite is the basic measurement instrument used in land surveying and construction. It allows measuring distances between points in the field based on angles measured and trigonometric calculations performed. The main parts of a theodolite are the base plate (for mounting on a tripod), limbus (circle plate) and the alidade, i.e. the turning part, which includes the scope, among other parts. The presented repetitive (bi-axial) theodolite in the field in reference to geographic directions. The instrument was made in the Fabryka Instrumentów Geodezyjnych Gustawa Gerlacha in Warsaw in 1938 or a little earlier. The establishment operated from 1816 to the World War II, and it specialised in producing land surveying instruments such as the theodolites, levellers, rangefinders, steel squares, and topographic tables. Manufacturer: Fabryka Instrumentów Geodezyjnych G. Gerlach, 1938 Inv. No.: MIM1255/XI-107 Model prepared on the basis of photogrammetric measurements. Licence: CC BY-NC-SA