NEIMME: Lamps
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No. 73. CLOWES HYDROGEN GAS TESTING LAMP. Click to view image |
The form of lamp used is the Hepplewhite Gray Lamp (No. 72.) with a lengthened glass and three air tubes.
The interior of the back of the glass is blackened to aid observation of the flame and caps. A metal scale behind the flame facilitates measurement of the gas cap.
A tube of very small bore passes through the oil vessel from the side and terminates near the top of the wick tube.
A portable steel cylinder containing compressed hydrogen attaches to the side of the lamp.
To test for small percentages of gas the hydrogen is turned on and lights from the oil flame which is extinguished by drawing down the wick and the test is made. On completion of the test the wick is pushed up and the oil flame is lighted by the hydrogen which is then shut off.