Antique late 1800's/early 1900's glass "The Allenbury's Feeder" still with original teat

The Allenbury's Feeder is an infant feeding bottle made by Allen & Hanbury's Ltd, London, a manufacturer that also produced its own infant foods and medicinal products during the late 1800's and early 1900's.  

The glass bottle is 20cm long to end of teat, boat-shaped with a flat base that allows it to remain stable when put down and still has it's original teat. The other opening originally had a rubber valve to control air flow but this inevitably was misplaced (as in this case) and the thumb was used instead. The feeder is embossed "The Allenbury's Feeder" and also with gradations in ounces and tablespoons for measuring content. It is also embossed with the patent number (15449), and design registration number (543283) and the number R.10690/23/1359. It is in very good condition with no chips or cracks and teat also has no damage.    Refer images