are bad noses,—­very bad noses, I assure you....  Do not, I pray you, consider me irreverent, if I say that Nosology will prove highly favorable to the cause of religion.  This is indeed an awful subject, and I would not touch it on slight grounds; but I sincerely believe that what I say is true.  Nosology will prove highly favorable to the cause of religion!  Does not the nose stand forth like a watchman on the walls of Zion, on the look-out for all assailants? and when our faces are directed upwards in devotion, does not the nose ascend the highest and most especially tend heavenward?...  Nosology is a manly science.  It stands out in the open light.  It does not conceal itself behind scratches and periwigs,—­nor does it, like certain false teachers mentioned by St. Paul, go about from house to house, leading astray silly women......Finally, gentlemen, you may rest assured that Nosology will not gently submit to insult. Noli me tangere! Who ever endured a tweak of the nose?  It will know how to take vengeance.  As Jupiter metamorphosed the inhospitable Lycians into frogs, so its contemners will suddenly find themselves [Greek:  Barbarophonoi]!”

Percival has been thought over-tenacious of his opinions.  He was certainly very circumspect in changing them.  I have witnessed, however, several instances in which he yielded to the force of evidence in the modification of his views.  He seemed to recognize geology, in particular, as a progressive science, in which new facts are constantly accruing, and therefore compelling re-adaptations of our views.  He felt, indeed, in respect to all knowledge, the mathematics excepted, that modifications of belief, in well-regulated minds, are unavoidable, as the result of new information.  Approach to higher truth through the sciences he seemed to regard under the aspect of that of besiegers to a beleaguered fortress.  Principles and deductions, which were a boon and a triumph for us yesterday, lose their value to-day, when a new parallel of approach has been attained.  He lost his interest in what was abandoned, necessary as it had been to the present position, only in the advantage of which, and its sure promise of what was still higher, he allowed himself to rejoice.

But where evidence was wanting, he was never to be moved to a change by any amount of importunity or temptation.  This trait of character made him somewhat impracticable as a collaborator, in the philological task he was employed to perform under Dr. Noah Webster.  Disagreements were to have been anticipated from the striking contrasts in their minds.  They agreed in industry; but Webster was decided, practical, strongly self-reliant, and always satisfied with doing the best that could be done with the time and means at command.  Percival was timid and cautious, and, from the very breadth of his linguistic attainments, undecided.  He often craved more time for arriving at conclusions.  When he happened to differ from the great lexicographer,