You’ve got an antique acoustic hearing aid trumpet—specifically the “London Dome” pattern used in Britain and exported to America from the late Victorian era into the 1930s.
A non-electrical acoustic hearing amplifier.
These were mass-market assistive devices before vacuum tube hearing aids existed.
Users pressed the rubber ear tip against the entrance of the ear canal while sound was collected and passively amplified inside the dome.
They’re cousins to:
• ear trumpets
• conversation tubes
• auricles
• “private listener” domes
The nickname refers to the bulbous, helmet-like collector popularized by British instrument makers.
These were sold by London shops such as:
• Acousticon (UK branch)
• Hawksley & Son
• Arnold & Sons
• S. Maw, Son & Thompson
Some American sellers imported them through Betterton & Co. The dome shape focuses sound waves toward the listening tube.
Think of it as a Victorian analog megaphone—but reversed.
The wide chamber collects ambient sound → narrows it through the tube → intensifies it at the ear.
Users often:
• held them under the chin
• slightly rotated to “aim” at the speaker
• tucked them into coat folds discreetly
Your features are textbook:
Rubber wasn’t used before ~1900.
The translucent aged tone suggests 1920s production.
Brass underneath (note the tarnish) = common from 1890–1930 inpatient/clinic models.
That scrollwork isn’t ornamental—it breaks up wind noise and prevents muffling.
This sits squarely in the:
1915–1930 period.
Tall domes increase:
• resonance chamber size
• low-frequency clarity (speech intelligibility)
• directional focus
These were surprisingly effective indoors.
Owners sometimes used them to:
• eavesdrop in theaters
• listen through thin walls
• hear distant radio cabinets
• spy on card table gossip
Victorians loved a gadget with social advantage.