BENJAMIN FRANKLIN. \j 



matters lighter than the central parts of that air, and immersed 

 in it, would recede from their centre, and rise till they arrived 

 at that region of the air which was of the same specific gravity 

 with themselves, when they would rest, while other matter 

 mixed with the lighter air would descend, and the two meeting 

 would form the shell of the first earth, leaving the upper atmos- 

 phere nearly clear. The original movement of the parts toward 

 that common centre would naturally form a whirl then, which 

 would continue upon the turning of the new-formed globe upon 

 its axis, and the greatest diameter of the shell would be in its 

 equator. If by any accident afterward the axis should be 

 changed, the dense internal fluid, by altering its form, must 

 burst the shell and throw all its substance into the confusion in 

 which we find it whereby the upturning and mingling of strata 

 so often found are explained. 



A paper in the Memoirs of the Literary and Philosophical 

 Society of Manchester, England, contains some meteorological 

 speculations and conjectures. It supposes a region high in the 

 air over most countries where frost exists continually. The 

 mass of the earth to the depth perhaps of thirty feet retains its 

 heat for some time. Hence the first snows are melted and the 

 beginning of the winter is slow. The cold of the winter of 

 i783~'84 was attributed, in accordance with this theory, to the 

 fogs that prevailed in the preceding summer, which prevented 

 the land being warmed as much as usual. 



A letter from M. de Saussure, the eminent Alpine geologist, 

 found among Franklin's papers, exhibits Franklin as interested 

 in the experiment for determining the density of the earth by 

 measuring the attraction of a mountain. The letter, in answer to 

 a proposition on the subject from the Royal Society, mentions 

 the difficulty of performing the experiment in Switzerland, on 

 account of the confusion of the attractions of surrounding 

 mountains, and suggests that it be tried on some high, isolated 

 peak. 



The alleged finding of some toads inclosed in solid stones at 

 Passy, near Paris, suggested a curious speculation as to the way 

 in which they could have lived under such conditions. " It is 

 observed," Franklin said, "that animals who perspire but little 

 can live long without food, such as tortoises, whose flesh is 

 covered with a thick shell, and snakes, who are covered with 

 scales which are of so close a substance as scarcely to admit 



