Not much is known about this English firm. 

According to Dr. John Bevan, this helmet was probably produced by mr. A.E. Stove of Applegarth and Stove, 11 Queen Victoria Street, London. The production date is sometime between 1888 and 1899. This helmet is shown in the companies patent drawings of 1888. Photo courtesy of Leon Lyons.

Stove in action!
Photo courtesy of our friend Mikael Zingmark