106 



ELEMENTS OF STATIC ELECTRICITY. 



the lower ends of which are immersed in cold water at 

 the bottom of the condenser : and the water being thus 

 raised by capillary attraction, cools the pipes, producing 

 partial condensation of the steam ; thus charging it 

 with water in fine drops, by the friction of which 

 against the pipes electricity is generated; the steam 



Fig. 35 Armstrong's Hydro-Electric Machine, 



being discharged against a row of points connected 

 with the prime conductor. 



Each pipe is furnished with a wooden tip : and the 

 friction is increased by a tongue of metal, around which 

 the steam must pass before entering the tip, as shown 

 by the enlarged section at letter A. 



A machine of this kind, constructed for the Royal 



