Carl Zeiss Jena Leveling Instrument NI.B. 1940s. Germany. Rough leveling is made possible by a circular level. Through an additional microscope, we observe a coincidence leveling toric level – the prism system maps the edges of the bubble into a single image. The toric level culminates when the edges are aligned. It is culminated by means of the tilting screw. The instrument has a telescope with internal focussing and a 35 mm objective with 31x magnification. The crosshairs are Reichenbach crosshairs. A level is an optical instrument used to establish or verify points in the same horizontal plane in a process known as leveling, and is used in conjunction with a leveling staff to establish the relative heights levels of objects or marks. It is widely used in surveying and construction to measure height differences and to transfer, measure, and set heights of known objects or marks. Carl Zeiss AG, branded as ZEISS, is a German manufacturer of optical systems and optoelectronics, founded in Jena, Germany in 1846 by optician Carl Zeiss. Together with Ernst Abbe (joined 1866) and Otto Schott (joined 1884) he laid the foundation for today's multi-national company. This Carl Zeiss Jena NI B level can be a great addition to any working tools collection.