322 Don J. Rodriguez’s Observations on the 
their imagination, was that which supposed the earth to be 
throughout composed of the same kind of matter, and its sur- 
face that of a spheroid generated by revolution round its axis. 
This hypothesis, adopted by Newton only as an approximation 
to the truth, is, in fact, perfectly consistent with the equilibrium 
to which particles in a state of paste, or of tardy fluidity, would 
arrive in a short time after their present motion was impressed ; 
and the eccentricity derived from this hypothesis is at least 
not very remote from that which actually obtains in the pre- 
sent state of consistence and stability which the earth has since 
acquired. 
But the homogeneity of the matter, of which the earth con- 
sists, is at variance with all geological observations, which 
prove evidently that at least 3000 toises of the exterior crust 
is formed of an immense mass of heterogeneous matters vary- 
ing in density from each other ; and upon the supposition of 
a state of fluidity of the whole, it should follow that the strata 
should successively increase in density from the surface to- 
wards the centre, that the more dense would accordingly be 
subjected to less of centrifugal force, and consequently that 
the spheroidical form resulting from this cause would be less 
eccentric than would arise from a state of perfect homoge- 
neity. 
The most simple, as well as the most effectual means of 
verifying the hypothesis respecting the figure of the earth, is 
to measure in the two hemispheres several arcs of its meri- 
dians in different latitudes, at some distance from each other. 
On this subject it must be allowed, that the Academy of 
Sciences at Paris set the example, in giving the original im- 
pulse to the undertaking, and not only commenced, but put 
