Date: 1919-1948. Owner unknown
This is an alto trombone, in Eb (which is customary). "Normal" trombones are in fact tenor trombones and are lower than an alto. The 16H has a #1 1/2 bore (0.459") and was built from 1919 to 1948. The instrument pictured above was probably built earlier rather than later on account of the bell engraving (not shown). There is also a 17H model, which is identical except it presumably has slides for both high and low pitch. From the picture it would appear that the tuning slide is in the hand slide and not in the bell crook. The advantage of this is that it allows the entire bell section to be smoothly conical without requiring a cylindrical section to allow for the tuning slide.