1886.] on the Electrical Deposition of Dust and Smohe. 529 



on our climatic conditions as to be now the main object of study with 

 meteorologists, since Mr. Buchan proved to us their existence and 

 showed us how to study them. Some of them are gigantic, but some 

 are small and almost local whirls. A long way we are at present 

 from even entertaining the idea of artificially controlling them ; but 

 we have learnt to control a great number of natural agents — torrents, 

 cataracts, fire, electricity ; and the main effect of a thunderstorm on a 

 civilised town is now merely to clear its air and stir up its lightning 

 conductors. Storms, earthquakes, and volcanoes we have not yet 

 learnt to control, perhaps we never shall. Perhaps also we may 

 always remain unable to exert any effect even on ordinary winds, 

 clouds, and rain ; but the interests involved at certain seasons of the 

 year in the presence or absence of a succession of rain-compelling 

 cyclones, or of frost- and sun-transmitting anti-cyclones, are so 

 prodigious, that even the barest glimpse of the possibility of exerting 

 any kind of effect upon these great agents is worth attention, and it 

 is a subject eminently suited for experiment. The experiments, 

 however, must be on a large scale, and must be costly ; were it not 

 so, I for one should not hesitate to make some preliminary attempts 

 in the direction indicated. 



Beferences to the Literature of the Subject. 



Proc. Roy. Inst. vi. p. 1 (1870), Tyndall (Discovery of dust-free space). 



Proc. Eoy. Soc. xxv. p. 542, Frankland (Brief). 



" Floating Matter of the Air," Tyndall, p. 5. 



Proc. Eoy. Soc. December 1882, or Nature, xviii. p. 139, Lord 



Rayleigh (Dark plane). 

 Nature, 26th July, 1883, xxviii. p. 297, Lodge (Preliminary Letter). 

 Nature, 31st January, 1884, Aitken (Abstract). 

 Phil. Mag. March, 1884, or Proc. Phys. Soc. February 1884, Lodge and 



Clark (Main paper, with plate). 

 Trans.R. S. Edin. xxxii. p. 239 (1884), Aitken (Main paper, with plate). 

 Minor Papers : 



Nature, 24th April, 1884, Lodge (Lecture to Eoyal Dublin Society, 

 on Dust- free spaces). 



Nature, 22nd January, 1885, Lodge (Lecture to Brit. Assoc. 

 Montreal, on Dust). 



Nature, xxix. p. 417, Lodge and Clark (Abstract). 



Engineering, 5th June, 1885, Walker. 



Engineering, 21st May, 1886, Wimshurst. 



La Nature, or Electrician, 21st May, 1886, Tissandier. 

 Nature, xv. p. 302 (1877), Crookes (Eepulsion by hot Surface). 

 Phil. Trans. 1879, ii. p. 727, Osborne Reynolds (Dimensional 



Properties of Gases). 

 Proc. Eoy. Soc. March and May, 1879, and June 1882, Lord 



Eayleigh (Liquid jets). 

 Brit. Assoc. Eeport, 1885, pp. 744 et seq. Lodge (Electrostatic view 



of Chemical Action). [O. L.] 



2 M 2 



