BAIRD &L TXTLOCK. (LONDON) LTD. 



5063 



5063 T Redwood's Inflammable Vapour and Gas Detector, with long flexible suction tube, 

 guaranteed to detect and accurately measure, by means of a hydrogen flame, small 

 percentages of inflammable gases or vapours . . . . . . . . . . 43 



DESCRIPTION OF THE APPARATUS. 



The appliances (see figure) consist of the testing lamp A, the reservoir of compressed hydrogen B, and the 

 sampling vessel c, in which the sample of air for examination is collected. 



The lamp is so constructed that flame cannot travel from the jet to an inflammable or explosive mixture in the 

 sampling vessel. The chimney, which is partly of metal and partly of glass, fits air-tight when in the position 

 shown in the illustration, butmay be raised to light the hydrogen flame or admit air. To facilitate the adjustment 

 of the size of the hydrogen flame the chimney is fitted with a sliding shutter, which is raised when working with 

 the larger flame and lowered when using the smaller. Attached to the base of the lamp is a telescopic support 

 for a cloth which envelops the head of the observer, and excludes light when the testing apparatus is used in an 

 undarkened room. 



The hydrogen reservoir is one of the cylinders ordinarily employed for compressed gas, and holds 5 cubic ft., 

 which is sufficient to supply the flame for at least ten hours. 



The collecting vessel consists of a compression pump, with metallic spring piston lubricated with plumbago, 

 surrounding which is an annular space in which the sample is compressed to 30 Ibs. per sq. in., a spring valve 

 opening at that pressure being provided. The vessel is fitted with inlet and outlet cocks, unions, and a pair of 

 hinged brackets on which the operator stands while working the pump. 



" Laboratory Book of Mineral Oil Testing," by James A. Hicks 

 (late Chief Chemist to Sir Boverton Redwood). Price 2s. 6d. 



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CROSS STREET HATTO>J GARDETST, E-C 





