VTG porcelain stamp and envelope moistener used in offices in mid 20th century

VTG porcelain stamp and envelope moistener, commonly used in offices during the mid-20th century to wet gummed adhesives.  Material: White glazed porcelain body with a rolling cylinder mechanism.  Function: Users would fill the trough with water, which would moisten the roller as it turned, allowing for mess-free application to envelopes or stamps.  Purpose: A practical tool designed for efficient mailing and documentation work.  Usage: A collectible piece of vintage office  See pic of chip on bottom. Not visible when displayed