832 Sketch of a General Theory of the [JuLy, 
cut; and they are, therefore, in'so far subject to similar laws with 
liquids contained in tubes. * ; 
It is, then, from Cuvier’s not distingaishing between the height 
and the breadth of the organs, and their corresponding intensity or 
permanence of function, that his comparison of man and the bull, 
and his scate in general, which Dr. Leach has quoted, is of dimi- 
nished value, and quite inapplicable to the present question. This 
curious and important fact may be illustrated even from the classes 
of animals; for the laterally compressed and high cerebellum of 
birds corresponds admirably with the inéensity of their voluntary 
_ powers, and the depressed and flaé cerebellum of the turtle, frog, 
salamander—in short, of all the slow but long moving reptiles; 
equally corresponds with the permanence of their voluntary power. 
In reply to Dr. Cross’s last observations (in the 30th number of 
the Annals), 1 need say little indeed. The strongest argument 
which he adduces in refutation of the preceding doctrine, is the 
ironical application of the words “ logical and sapient,” and the 
direct one of the words “ absurd and groundless.” Now whether 
Dr. Cross’s authority in matters of science is sufficient to render 
such words, when used by him, the very death-warrant of a new 
doctrine, I am perfectly ignorant; but, with me, even much 
higher authority than the Doctor’s would not constitute proof. Dr. 
Cross adds, “ that volition ranks among the faculties of the mind, 
whose organ is the cerebrum ;” and so far as authority in general 
and the authority of Dr. Cross in particular goes, this is another 
proof of the falseness of my doctrine. The Doctor, however, fur- 
ther adds, “ that atfections of the cerebrum, while the cerebellum 
remains sound, produce palsy, which I humbly submit is just a loss 
of volition.” At last, then, the Doctor does give us an argument} 
and as it isa solitary one, and follows so much of mere authoritative 
determination, it must no doubt be so triumphant that the “ humble 
submission” which the Doctor forgot when adducing his authority, 
but so generously appends to his proof, must be intended only to 
enhance talent by modesty, and to heighten trizmph by moderation. 
This is certainly very fine ; and it involves only one little awkward 
circumstance, which is, that while the Doctor’s proof consists of 
two propositions, it presents precisely as many errors! “ Affections 
of the cerebrum,” says he, “ while the cerebellum remains sound, 
produce palsy;” and hence he means to conclude that palsy which 
he deems a loss of volition, and consequently volition itself is de- 
pendent on the cerebrum, and not on the cerebellum: indeed he 
actually says so in the preceding portion of the same sentence; thus 
placing the induction (logically no doubt) before the datum, and 
® It is perhaps also for the same reason, that, in a galvanic battery, the in- 
tensity of its action seems to correspond with the number of the plates (for the 
ignitiug power is as the number), and the permanence of its action with the mag- 
nitude of the plates. Accordingly, M. de Luc observes that the number of the 
plates is analogous to the length of a pump for raising water ; and the size of the 
plates is analogens to the magnitude of the bore of the pump. 
