366 Transactions. — Miscellaneous, 



This is a convenient one in many difficulties. Here is something we cannot 

 understand. It must, therefore, be caused in some way by that mysterious 

 force, electricity — which in the near future is to produce for us, even artifi- 

 cially, light, heat, motion, and every form of energy. As is the super- 

 natural to one class of people, so is electricity to another, wiser in its own 

 eyes — a key to unlock every dark and mysterious chamber in the universe. 

 And when we consider what electricity has enabled us to do in recent times, 

 we cannot wonder that it should be credited with effects for which it is not 

 at all responsible. 



I. — The Cosmic Dust Theory. 

 But now we must pass to theories which are more plausible ; and the 

 first of these is that the earth has been recently passing, particularly in its 

 intertropical parts, through some meteoric region or a cloud of cosmic dust. 

 But those who advance this, forget to tell us how it is that there has been 

 even less than the usual number of shooting stars during the period of the 

 glows. The dust in the upper air was once thought to come from outside space 

 and to be the residuum of burnt-out meteors. Some of these erratic bodies 

 rushing aimlessly through space are, from to time, caught by the gravitation 

 of the earth, and then in their rapid passage towards its centre, striking the 

 air, acquire such intense heat that they burst after a very brief moment of 

 incandescence into vapour and are burnt out 60 miles above the level of the 

 sea (Banyard, " Knowledge "). Now, if we had been passing lately 

 through such a meteoric belt as is supposed, during the numerous clear 

 nights that we have had, meteors or shooting stars such as I have described 

 must have been seen in considerable numbers. As a matter of fact none, 

 or next to none, have been visible. Lockyer, Banyard, and Williams, 

 nevertheless, were at first inclined to this theory — the latter gentleman 

 more especially — in consequence of the results obtained through examina- 

 tion and analysis of the dust gathered from melted snow ; and Mr. Ellery 

 stated, in an address to the Boyal Society of Melbourne on 15th November, 

 that there were only two admissible theories to account for the sun-glows, 

 and one was that the earth was passing through a meteoric region resulting 

 in refraction of the sun's rays. Mr. Banyard says (" Knowledge," 14th 

 March) that at first he could not resist the impression that the glows were 

 caused by meteoric dust, though he knew well enough that in 1861 the earth 

 passed directly through a comet's tail without any such glows appearing. 

 But all these gentlemen abandoned this theory subsequently. A Mr. Biggs, 

 of Launceston (Tasmania), says that if we had been running through a 

 meteoric belt such as is supposed, the meteoric bodies would have been 

 falling upon us at the rate of 200,000 miles a day — that celestial fireworks 

 would have been astonishing, and that everything sublunary would have 



