F. E. Brandis, Sons & Co., which was in business as such during the period 1890-1916, described this instrument as an Engineers' Transit with Level Attachment, Gradienter, and Vertical Arc. The horizontal circle is graduated to 20 minutes of arc, and read by opposite verniers to 30 seconds. The vertical arc is graduated to 20 minutes of arc, and read by vernier to single minutes. New, it cost $239.
Ref: F. E. Brandis, Sons & Co., Illustrated and Descriptive Catalogue and Hand-Book of Instruments of Precision for Civil Engineers, Surveyors and Astronomers (New York, 1902), p. 163.
Charles Smart, The Makers of Surveying Instruments in America Since 1700 (Troy, N.Y., 1962), pp. 14-15.