No. 53.
ASHWORTH HEPPLEWHITE GRAY LAMP.
Presented by T.E. Foster.
Made by Stanley, Derby.
CONSTRUCTION.
Gauze. 28 mesh iron.
21/2 ins. high.
Above the gauze there is a conical restriction in the chimney down to ? ins diameter.
Burner. ? ins flat wick.
Lock. Screw.
Glass. Tapers from 2 ins to 1 ins internal diameter.
Air inlet is from the four hollow standards which can be opened or closed at the top by sliding the crown of the lamp round. This facilitates gas testing near the roof. Slides at the bottom of two of the standards enable air to be taken in there if necessary. The intake air passes through a small gauze cylinder in the bottom ring and thence to the flame.
HISTORICAL NOTE.
This lamp is a development of the lamp patented by Mr. T. Gray in 1868.
It was designed primarily for 'fire-triers' use.
The sliding ferrules were patented by Mr. J. Ashworth in 1887.