A directional timepiece with a diverse set of applications, this equatorial sundial and compass was made by the company of Tangate of St. Petersburg. The original wood case measures 9 x 9 x 2 ½ inches and has the makers’ label as well in English and Russian, stating Tangate as a "Mathematical & Optical Instruments Maker" located in No. 77, "opposite the Catholic Church".

The sundial arm measures 3 inches in length and the instrument is signed in the ring margin as well.