BAIRI) & IATLOCK (LONDON) LTD. 



, 



5970-5971 



5972-5973 



5975 



5970 Apparatus to prove that it is only the external envelope of a flame that is hot, and that 



the centre remains cool. Without stand . . . . . . . . . . - - 030 



5971 Stand with clamp . . . . . . . . . . . . . . ..070 



Consisting of a glass cylinder with wire cap at top, and with cork at lower end, through which passes a glass 

 tube. A small quantity of gunpowder or the heads of matches is placed in the centre of the wire cap, and gas 

 admitted by the glass tube at bottom. When the gas has expelled all the air from the tube, light from above. 



5972 Apparatus to burn oxygen in hydrogen or illuminating gas. Without stand . . . . 060 

 Consisting of two glass lamp chimneys connected at bottom by a piece glass tubing ; into each cylinder is also 



led at bottom a narrow glass tube. To manipulate, close one cylinder (A) at top with a cork.and lead into it (a) 

 hydrogen until all the air is driven out and hydrogen begins to come into the other cylinder, when apply a light 

 to it at b', removing the second cylinder (B) for that purpose. Before replacing the second cylinder (B), lead 

 oxygen to it (6) and regulate the flow of hydrogen by a pinchcock. In order to drive the flame from the second 

 (B) into the first (A) cylinder, take the cork out of the first (A) and put it into the second (B) cylinder, whereby the 

 hydrogen flame in the second cylinder (at b') becomes smaller, slips into the tube, and appears as an oxygen flame in 

 the first (A) cylinder (at a'). This flame can also be regulated by a pinchcock. (Two cylinders, two corks, and 

 indiarubber stopper tube with platinum point.) 



5973 Stand with double clamp, two pinchcocks, and indiarubber tubing . . . . . . 16 6 



Coal gas is introduced into the bulb by the side tube in neck, and after all air has been expelled, the gas 



escaping at top tubulure is lit and the air tube slipped down through cork to centre of the bulb, where it will 

 continue to burn. 



5974 Apparatus by Kekule, to light one gas in an atmosphere 



other than the air by means of the electric spark . . 12 



For example, to burn hydrogen in oxygen or chlorine ; chlorine gas in 

 hydrogen ; illuminating gas or ammonia in oxygen. Consists of a flask, 

 capacity about i litre, with two tubes and neck, all fitted with indiarubber 

 corks. Through the neck, which is placed mouth downwards, two tubes are 

 passed, one short, the other long, and reaching to about a third of the 

 diameter of the flask. By one tubulure the two platinum wires are led to 

 near the top of the long tube, which enters from the bottom. Through the 

 other tubulure a short glass tube is inserted. If it is desired to burn oxygen 

 in illuminating gas, the gas is led into the flask by the tubulure at side, and 

 when all the air is expelled, oxygen admitted by the long tube through the 

 neck is lit by the electric spark at the burner, the wires being at once drawn 

 back to avoid injury. The gas which is to form the atmosphere is led into 

 the flask by the tubulure at the side when it is heavier, and by the neck 

 when it is lighter than the air. (Flask, three indiarubber corks, tubes, and 

 5974 platinum wires.) 



5975 Lecture Apparatus, for showing combustion of air in an atmosphere of coal gas, etc., 



by Mr. George Craig (see Chemical News, 3rd August, 1888) . . . . . . 040 



1086 



