34 



" On the Electrical Properties of Clouds and the Pheno- 

 mena of Thunder Storms," by Professor Osborne Reynolds, 

 M.A. 



The object of this paper is to point out the three following 

 propositions respecting the behaviour of clouds under con- 

 ditions of electrical induction, and to suggest an explanation 

 of thunder storms based on these propositions and on the 

 assumption that the sun is in the condition of a body 

 charged %vith negative electricity : an assumption which I 

 have already made in order to explain the Solar Corona, 

 Comets' Tails, and Terrestrial Magnetism. 



1. A cloud floating in d,ry air forms an insulated electri- 

 cal conductor. 



2. When such a cloud is first formed it will not be charged 

 with electricity but will be ready to receive a charge from 

 any excited body to which it is near enough. 



3. When a cloud charged with electricity is dAminished 

 by evaporation, the tension of its charge will increase until 

 it finds relief 



I do not imagine that the truth of these propositions will 

 be questioned, but rather, that they will be treated as self 

 evident. However, as a matter of interest I have made 

 some experiments to prove their truth, in which I have 

 been more or less successful. 



Experiment 1 was to shew that a cloud in dry air acts the 

 part of an insulated conductor. The steam from a vessel of 

 hot water was allowed to rise past a conductoi-, the apparatus 

 being in front of a large fire, so that the air was very dry. 

 When the conductor was charged the column of vapour was 

 deflected from the vertical to the conductor both for a posi- 

 tive and negative charge. 



Experiment 2 was made with the same object as Experi- 

 ment 1. A gold leaf electrometer was charged so that the 

 leaves stood open and then a cloud made to pass by the insu- 

 lated leaves. As the cloud passed they were both attracted. 



