Ferdinand Hell, Vienna c.1854? (in restoration)(Magee)
 

Having just come in from Europe it had to settle after the first winter here. It will need a full internal restoration to make it ready for playing. Then the bass will get a KS/USA style set-up like all the other double basses in the racks in my showroom.

From Cecie Stainer, "A dictionary of violin makers" 1896;
A maker in Vienna. In 1854 he exhibited in Munich a double-bass of rather small pattern, but of powerful tone. He is also the inventor of the trumpet-violin, an instrument which can be used as a trumpet or as a violin equally well. (Could this be 'that' Bass?)

When it returns from restoration, it will be ready for professional use.

Here are some pics (pre-restoration) and measurements of the Hell bass.

Measurements:
String Length; 41 1/8"
Top/Back Length; 41" top, 42 3/4" back
Upper Bout; 19"
Middle Bout; 14 1/2"
Lower Bout; 25 1/8"
Ribs; 7 3/4", 5 3/4" at neck