166 Mr. K. M'fbsttr on ihe Causes 



own specific gnivity, before any organic matter had existence; 

 and if a fluid, from any cause but fire, organic matter may 

 have had existence, in the hitter it is impossible. Assuming as 

 a fact the earth was in its first formation a fluid, by excess of 

 heat, the denser bodies, as the metals, iron, &c. woukl, by the 

 power of gravity, compose tlie centre of the eartli, au'.i gra- 

 dual and partial coolings taking place, on the exterior suriace, 

 before the interior, would of necessity cause violent explosions 

 and convulsions, throwing the earth into variety of mountains 

 and valleys : metallic matter would retain its liquitl state long 

 after what I assume as the substance composing the outer 

 crust of the earth, namely, what the geologist calls primary 

 rocks, had formed itself; and as it dried it would contract, and 

 cause large fissures, in which the metallic fluid may have been 

 driven in the diurnal revolution of the whole on its axis, 

 nu'.king the veins of metals which intersperse the surface of 

 tlie globe. Admitting the outer crust would be complete long 

 before the interior was cool, a position self-evident, metal- 

 lic fluid would occupy a nuich hu'ger space than when con- 

 centrated into a solid mass, and between this solid and the 

 outer crust is an immense body of water, having sunk fi'om 

 the earth's surface as the sj)ace between the centre sphere and 

 it became unoccupied by the concentration ot fluid into sub- 

 stance which had for ages during the period of cooling, as 

 the lighter body, surrounded the whole. I need not say 

 much upon the probability of water for a very long period 

 covering the earth, it being evident I'rom the immense dejjosit 

 of shells in everj' part of it. I shall assert iron to be a very 

 large component part of this inner sphere, as it is admitted to 

 be the most universally diffused substance in nature; it must 

 also form a component part of some other planet or portion of 

 the system of which this earth is but a trifle, as it is known 

 that all the meteoric substances that have fallen on the earth 

 bear the proportion of nearly nine-tenths of iron to one-tenth 

 of the scarce metal called nickel. 



Having said thus much as a prelude to my hypothesis on 

 the causes of the variation of the needle, and assuming still, 

 this inner sphere to be suspended or rather inclosed in fluid, 

 it would revolve on its axis with the earth ; yet with a pro- 

 gressively less motion, falling backwards in its course each 

 successive day, that would amount to one entire retrograde 

 revolution in 584- years ; and this may be readily conceived, 

 that an interior ball suspended in fluid may not equal the 

 outer in a rotary motion. I would now fix the north mag- 

 netic pole about 72° 40' north latitude, and 100° 30' west 



longitude, 



