This cast-iron valve installed on the Prospekt helped regulate the volume of steam in the Tramway plant’s pipeline. Like the one displayed on the Square, this valve was manufactured between 1897 and 1917 at the Gustav List mechanical factory, which was located next door on the Sofiyskaya Embankment. The state emblem on the valve was then the equivalent of a quality mark. The handwheel—or, as it is also called, the flywheel—of this valve can be rotated.
Gate valve. Prospekt