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Domestic Science 



a number of powerful Bunsen burners. (In the diagram 

 the tube is shown above the iron trough, but should lie 

 in contact with it while in use.) A bent glass tube 

 connects the flask with the long tube, and a glass 

 delivery tube leads into the water in an earthenware 

 trough. Having fitted up the apparatus as figured and 

 described, light the burners under the flask and tube, 

 the flask being temporarily disconnected from the tube. 

 When the bed of the furnace is at a dull red heat, and 

 the water has reached boiling-point, attach the flask 

 once more and allow the steam to pass through the tube. 

 After allowing an interval of about two minutes for the 



Fig. 91. 



escape of most of the air from the apparatus, place an 

 inverted gas- jar full of water over the hole in the bee- 

 hive cell. Bubbles of gas rise to the top of the jar, 

 which is rapidly filled. Collect another jar in the same 

 way. To show that hydrogen is contained in the jars, 

 put a lighted taper to the mouth of one, held in an 

 inverted position, and the gas will burn at the mouth 

 of the jar. Place the other jar on the bench, remove 

 the glass plate, and leave the jar with its mouth open 

 and directed upwards, for 30 seconds. A lighted taper 

 then plunged into the jar will not cause any sign of 

 ignition of hydrogen to be noted. As we shall show 



