94 Proceedings. 



3. " The Evidences of the Condition of the Interior of the Eartli.'" 

 by M. A. Eliott. 



Abstract. 



1. Gravitation proves that the total mass of the earth is 5^ times heavier than 

 water, the weight increasing towards the interior, the surface being from 2^ to 3^. 

 and the interior more than 8 times heavier than water. 



2. The shape of the earth shows that the density of the mass increases towards 

 the centre, and in such proportion that the rocky shell must be from 800 to 1,000 

 miles thick. 



3. (a.) The tides prove that the globe as a whole must be as rigid as steel, 

 though at the same time flexible, the core being 4 times as rigid as steel, [h.) Polar 

 oscillations show that the interior is of a plastic nature. 



4. Earthquakes prove that at a depth of 950 miles — i.e., the point of passage 

 from the rock mantle to the metal core — a sudden change occurs in the condition 

 of the strata. 



5. The temperature increases rapidly towards the centre, probably to thousands 

 ol: degrees, liquefaction, however, being prevented by the enormous pressure. 



6. The moon, formed from the same materials as the outer layers of the earth, 

 is known from astronomical observations to have a density of 3'4. coinciding exactly 

 with the average density of the rocky mantle. 



Thus the final conclusion is that the earth consists of a metal core, composed 

 principally of iron, with some alloy of heavier metal, as nickel, surrounded by a 

 rocky mantle about 9.50 miles thick. 



Election of Officers for 1911. — -Vresident — Captain Hewitt, R.N. ; 

 Vice-Presidents — Messrs. K. McNab and R. Gardner: Secretary and 

 Treasurer — Mr. K. Wilson; Auditor — Mr. J. Mitchell; Council — Messrs. 

 Barnicote, Bendall, Durward, Eliott, Sinclair, and Yernon. 



