No. 47.
WILLIAMSON LAMP.
Presented by T.E. Foster.
Made by Edwards, Wakefield.
CONSTRUCTION.
Gauze. 28 mesh iron.
Concentric with the gauze is a perforated thin copper plate with perforated cap. The bottom 1 inch of plate is not perforated.
Lock. Screw.
Burner. 1/4 ins. round wick.
Air intake is by small holes under the middle ring, through a gauze to the flame.
HISTORICAL NOTE.
This lamp patented in 1878 is one of several modifications made by J. Williamson of Cannock and Rugeley Collieries.
No. 48.
WILLIAMSON LAMP.
Presented by T.E. Foster.
Made by Edwards, Wakefield.
CONSTRUCTION.
Externally this looks very similar to No. 47. Internally it is quite different.
Gauze. 28 mesh iron.
Glasses. There are two concentric glasses, the inner one being 2 ins taller than the outer. The inner glass has a perforated copper cap.
Lock. Screw.
Burner. 1/4 ins. round wick.
Air intake is from the bottom of the outer gauze, down between the glasses through a gauze in the bottom ring, to the flame. It is augmented by air from holes under the bottom ring.
(See description of No. 47.)