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FiR. 1 



to conduct liquid air from a larger stock into the bottle. With the 

 cap a closed glass tube h is connected, in which an index of a 

 cork float dr indicates the height of the liquid. 



The caps, as shown in fig. 1, were formerly blown of glass and 

 the three tubes were fastened into it by means of india rubber. After- 

 wards the cap Aj, as shown in fig. 2, with the three tubes and with 

 a double wall li^ of very thin new-silver have been soldered to form 

 one whole, which is fastened on the bottle with an india rubber 

 ring /:. The space between the walls is filled with capoc h^ and the 

 whole piece rests on the neck of the bottle by means of a wooden 

 block i. After it is placed on the bottle the cap is wrapped round 

 with wool. 



With a view to ihe transport the vacuum glass is placed in a 

 card-board box with fibre packing. 



When the siphon is not used it is closed witii a piece of india 

 rubber tubing, fitted with a small stopper. When we wish to 



