200 THE FOREST LANDS OF NORTHERN RUSSIA. 



of the statements which follow, I may be allowed to intro- 

 duce the following statements. According to what was 

 advanced by Laplace as a hypothesis, but which has come 

 to be extensively accepted as a theory, the material of 

 which the earth consists was once floating in space in 

 widely separated masses, amongst which was in operation 

 what is known as the force of gravitation, under the influ- 

 ence of which, once and again and a thousand times told, 

 two or more of these separate masses, reciprocally attracted, 

 would coalesce, and if they happened to approximate, each 

 other in a line diverging in the slightest degree from that 

 of a straight line between their centres of gravity, which 

 would occur in the vast inexpressibly vast majority of 

 cases, they would begin to rotate around each other in a 

 curve which would most likely lead to their conjunction, 

 when the movement would issue in a rotary motion of 

 the composite mass. This composite mass would in like 

 manner come under the reciprocal attraction of other 

 masses, single or composite, until the whole, or the greater 

 part of the whole, mass of matter within the sphere of 

 attraction would be condensed into a large rotating mass ; 

 from this as the floating mass became further condensed, 

 portions un the outer circumference would be thrown off 

 by circumfugal force, as is a stone from a sling, or drops of 

 water from a mop which is made to rotate rapidly; but 

 these again would be gathered into smaller rotating 

 masses, which would revolve around the central mass, 

 which would finally be condensed as is the sun, while 

 these smaller bodies would be condensed as are the planets, 

 each rotating at the distance from the sun at which it was 

 thrown off ; and they, in the course of their condensation, 

 would throw off lesser masses, condensing into satellites or 

 moons, or into elongated masses, like the rings of Mercury. 

 Again, not to do more than merely mention the pheno- 

 mena of volcanos, there are in many rocks appearances 

 which have led careful observers of them to conclude that 

 what is solid of the earth is a mere crust around a mass 

 of molten matter ; and modern science tends to show that 



