As you might expect, the Bowers Encyclopedia has a lot of information
about the Adler (Eagle) and the Fortuna disc boxes once made by Jules
Heinrich Zimmermann, Leipzig.  On p. 242 he illustrates the No. 370
and the No. 375 (the 375 is simply the 370 with added base cabinet),
and quotes at length from Arthur W.J.G. Ord-Hume, who owns a 370.

Bowers states that there is no difference between the Adlers made by
Zimmermann and their Fortunas, except for the name.

Matthew Caulfield (Irondequoit, N.Y.)