A large two piece ear trumpet constructed from tin with a multiperforated grille.
An advertisement reads: “The dipper is the most powerful instrument, best adapted to hear public lectures or sermons and will be found efficient where the smaller-sized ear trumpets have failed. They differ from the ordinary ear trumpet in shape and construction. The mouthpiece is closed by a perforated metal plate. The neck is at a rightangles to it and reaches clear inside, in a curved line, nearly striking the bottom. Air waves passing through the little apertures of the mouth-piece will touch the bottom which, being a form of parabola, reflects them toward a common centre. This common centre is the neck of the instrument. All of the waves being forced into this channel and conducted to the ear, will operate with increased power.”
And true to the claims, because of the relatively large collecting dish the Big Dipper does work as and effective, if rather cumbersome aid to hearing. The extended length is 56 cm
- From the Phisick collection