CHAP, i.] ELECTRICITY AND MAGNETISM. 



49 



which served as prime-conductor, upon a glass pillar. 

 The nozzles were made of wood, perforated with a 

 crooked passage in order to increase the friction of 

 the jet against the sides. 



Fig. 28. 



45. Convection - Induction Machines. There 

 is another class of electrical machine, differing entirely 

 from those we have been describing, and depending 

 upon the employment of a small initial charge which, 

 acting inductively, produces other charges, which are 

 then conveyed by the moving parts of the machine to 

 E 



