Date: 1920. Owned by Stan Kling
The 18H Tait model was produced between 1919 (possibly earlier) and 1924. It has the main tuning slide in the hand slide. The advantage of this is that it allows the entire bell section to be conical without requiring a cylindrical section for the tuning slide. In 1924 the 18H was renamed "Frisco" and sold under that name until 1931.
The bore size of the 18H is something of a mystery. It is listed as having a #3 (0.500") bore. However, the owner of the instrument pictured here tells me that his trombone is a 0.458" bore (#1½) and has a 6" bell. It is also stamped "TAIT" and otherwise matches the description and pictures of an 18H exactly.