VI. CURRENTS. 325 



b. CHEMICAL EFFECTS. 



1391. Apparatus for the polar Decomposition of Water by 



means of atmospheric electricity or the currents of the ordinary 

 electrical machine. The gases are collected in fine thermometer 

 tubes, by which means their absorption by the electrolyte is avoided. 



Dr. Andrews, F.R.S. 



1391a. Warmbrunn, Quilitz, and Co.'s Apparatus for 

 Decomposition of Water, peculiar construction, with gradu- 

 ated tubes for the separated gases and for detonating. 



Warmbrunn, Quilitz, $ Co., Berlin. 



1392. Bottle, containing fragments of pure Electro- 

 deposited Metallic Antimony. George Gore, F.R.S. 



{See Philosophical Transactions of the Royal Society, 1857, 1858, and 

 1862.) 



1393. Two Specimens of Electro-deposited Antimony; 



one of the explosive, arid one of the pure variety. 



George Gore, F.R.S. 



1394. Hare Specimen of pure Carbon, deposited by 

 means of an electric current upon a rod of platinum. 



George Gore. F.R.S. 



c. ELECTRIC DIFFUSION AND CHANGE OF SURFACE-TENSION. 



1395. Apparatus for producing Vibrations and Sounds, 



and an intermittent electric current by means of the electrolysis of 

 a solution of cyanide of potassium and mercury with electrodes of 

 mercury. . George Gore, F.R.S. 



The effects are produced by the alternate rapid formation and destruction 

 of films upon the positive electrodes. {See Proceedings of the Royal Society, 

 Vol. 12, p. 217.) 



1395a. Electro Capillary Force Machine, after Lippmann. 



R. Jung, Heidelberg. 



To set this machine in action, the two wide glass vessels are first filled 

 to a height of 1 to 3 cm. with mercury, placed in position in the glass trough, 

 and then two thirds filled with pure dilute sulphuric acid. Then the two bundles 

 of thin glass tubes are pushed repeatedly down into the mercury, so that the 

 air is driven out, and the tubes and their interstices are quite filled with 

 mercury and acid. The bundles are then fixed by screws to their frames, 

 so as to be about half immersed in the mercury, and to stand in equilibrium in 

 the middle of their respective vessels. If the cups of the key be now filled 

 with mercury, and the crank, which works it, so placed that the current is 

 reversed a little before the opposite crank comes to its dead point, the machine 

 (having been connected with the poles of a Daniell battery) will commence 

 working, and may make as many as 100 revolutions in a minute. A Meidiii- 

 ger element keeps the machine in action for months. 



