56 MEMOIR OF PALLAS. 
purchaser, at the same time desiring him to make 
out the catalogue and fix the price. He accordinely 
named fifteen thousand rubles. Having examined 
the catalogue, she subjoimed, with her own hand, 
‘“* Mr Pallas understands natural history much bet- 
ter than figures: he ought to have charged twenty 
thousand instead of fifteen thousand rubles, for so 
many valuable articles. The Empress, however, 
takes upon herself to correct the mistake, and hereby 
orders her treasurer to pay twenty thousand. At 
the same time, Mr Pallas shall not be deprived of 
his collection, which shall still continue in his own 
possession during his life, as he so well understands 
how to render it most useful to mankind.” 
It has been acutely observed, that it rarely hap- 
pens that men who are very assiduously occupied in 
such multifarious enterprises have the requisite op- 
portunities and powers for originating those master 
ideas which effect great changes in the sciences ; 
but Pallas was an exception to this rule. It has 
already been noticed that he all but changed the 
face of zoology ; and it has been stated upon high 
authority, that he was really the instrument of 
effecting a revolution in geology, concerning what 
has been called the theory of the earth. An atten- 
tive examination of the two great mountain ranges 
of Siberia, led him to the recognition of this general 
rule, which has since been universally verified, that 
there is a regular succession in the three primitive 
orders of mountain rocks, viz. that there is a granite 
in the middle, then schists lying upon it, and, 
