This distinctive rounded top bonnet was designed and patented by Joesph Nicholson Guy of Gosforth, Newcastle, in 1894. Designed to be strong and lightweight, the bonnet was spun from a single piece of metal.
Joseph Guy became managing director of John Mills & Sons in 1896, and the company held the sole right to produce the patented shield. The company used this bonnet on several varieties of lamps, including their Mueseler, Clanny and Marsaut
