[ 17 ] 
III. Experimental Researches in Electricity. — Eighteenth Series. 
By Michael Faraday, Esq., D.C.L. F.R.S., Fullerian Prof. Chem. Royal Insti- 
tution, Corr. Memb. Royal and Imp. Acadd. of Sciences, Paris, Petersburgh, 
Florence, Copenhagen, Berlin, Gottingen, Modena, Stockholm, 85c. 8?c. 
Received January 26, — Read February 2, 1843. 
§ 25. On the electricity evolved by the friction of water and steam against other bodies. 
2075. TWO years ago an experiment was described by Mr. Armstrong and others*, 
in which the issue of a stream of high pressure steam into the air produced abundance 
of electricity. The source of the electricity was not ascertained, but was supposed to 
be the evaporation or change of state of the water, and to have a direct relation to 
atmospheric electricity. I have at various times since May of last year been working 
upon the subject, and though I perceive Mr. Armstrong has, in recent communi- 
cations, anticipated by publication some of the facts which I also have obtained, the 
Royal Society may still perhaps think a compressed account of my results and con- 
clusions, which include many other important points, worthy its attention. 
2076. The apparatus I have used was not competent to furnish me with much 
steam or a high pressure, but I found it sufficient for my purpose, which was the in- 
vestigation of the effect and its cause, and not necessarily an increase of the electric 
development. Mr. Armstrong, as is shown by a recent paper, has well effected the 
latter-f-. The boiler I used, belonging to the London Institution, would hold about 
ten gallons of water, and allow the evaporation of five gallons. A pipe 4^ feet long 
was attached to it, at the end of which was a large stop-cock and a metal globe, of 
the capacity of thirty-two cubic inches, which I will call the steam-globe, and to this 
globe, by its mouth-piece, could be attached various forms of apparatus, serving as 
vents for the issuing steam Thus a cock could be connected with the steam-globe, 
and this cock be used as the experimental steam-passage; or a wooden tube could 
be screwed in ; or a small metal or glass tube put through a good cork, and the cork 
screwed in ; and in these cases the steam way of the globe and tube leading to the 
boiler was so large, that they might be considered as part of the boiler, and these 
terminal passages as the obstacles which, restraining the issue of steam, produced any 
important degree of friction. 
* Philosophical Magazine, 1840, vol. xvii. pp. 370, 452, &c. f Ibid. 1843, vol. xxii. p. 1. 
1 This globe and the pieces of apparatus are represented upon a scale of one-fourth in the Plate belonging to 
this paper. 
MDCCCXLIII. 
D 
