1876.] Mr. W. Spottiswoode on Stratified Discharges. 79 



the diameter o£ which varied from capillary size to ^ inch, the capillary- 

 end being at the bottom. The positive terminal is at the top. The 

 principal interest of this tube consists in showing the influence of dia- 

 meter upon the velocity of proper motion. The wider the tube the 



Kg. 3. 



freer, it seems, the striae are to move. The same fact may be observed 

 by comparing tubes differing in diameter, but in other respects the 

 same ; but the conical tube brings out the fact in the most striking 

 manner. 



Fig. 4 represents a chloroform-tube, in which a piece of cotton-wool 

 had been inserted with a view of ascertaining whether any motion would 

 be communicated to it by the current. This proved to be the case ; but 

 I do not attempt here to describe the phenomenon. To the unassisted 

 eye the discharge was extremely brilliant ; it passed in a column not 

 quite straight, but in a writhing snake-like curve, with flaky strise at 



Fig. 4. 



