210 WARREN UPHAM, M.A., F.G.S.A., ON THE NEBULAR AND 



Mr. Tuckwell to the idea of highly heated matter revolving in the 

 low temperature of space can scarcely be reconciled with the 

 existence of the sun surrounded by space, and while agreeing with 

 Professor Lobley that volcanic action does not originate at great 

 depths below the earth's crust, there are zones of matter in a molten 

 condition due to intense heat or otherwise, how could we account 

 for the eruption of basaltic lavas (of several varieties it is true, but 

 essentially similar in composition) at widely distant places over the 

 whole globe for example, the British Isles, Central Europe, Sicily, 

 India, America and Iceland 1 



Communications. 

 From Rev. A. Irving, B.A., D.Sc. • — 



Regretting my inability to be present at the reading of Mr. 

 Warren Upham's paper on the " Nebular and Planetesimal Theories 

 of the Earth's Origin," I beg to offer a few remarks as brief as 

 possible thereupon. 



Starting with the "protyle" (or prothyle) hypothesis of Sir 

 William Crookes, F.R.S., I have preferred to regard the nebulous 

 matter as entirely in its origin non-differentiated ; while it is to the 

 teaching of the "periodic" or natural system of the elements (now 

 so well known to chemists) that we must look for light upon the 

 genesis of the elements (so far as they are known) out of which our 

 planet, with its four components, the barysphere, the lithosphere, 

 the hydrosphere and the atmosphere, is made up. We thus suppose 

 a stage at which the nebulae consisted of matter in a state of 

 elemental dissociation. By integration of the atomic matter further 

 differentiation proceeded, gravitation came into play as a nucleus 

 was formed with transformation of potential energy into heat, with 

 its expansive force, and dissipation of that energy into space by 

 radiation. These briefly — it is here submitted — are sufficient to 

 account for the inorganic evolution of the globe, when we take into 

 account the selective action of the chemical affinities of the atoms. 

 From such general data I attempted to work out in the " eighties " 

 an outline of the history and genesis of the present order of 

 inorganic nature as that presents itself on our planet, in accordance 



