1814.] on Transithn "Rocks. 298 



far as he was able, to promote ihe study to which we are equally 

 devuted." Now Mr. Allan will pardon me for saying so, but 1 do 

 think there is here something like a want of decorum; — something 

 like an aitempt to undtr-raie the exertions and merits of Pror 

 fessor Jameson as a mineralogist. But wlio that knows him, who 

 that knows any thing of the science, is not aware that his writings 

 and labours of various other descriptions, have been of incalculable 

 b.netit to it in this country. It will be allowed by most people, I 

 believe, that he is in a great degree the founder of mineraiogical 

 science among us. 



After the very trite observation, *' that it is much easier to find de- 

 fects in a system than to invent a better one," Mr. Allan speaks of 

 " incontrovertible points," and of '' descanting solely on their 

 weaker neighbours." He would have us admit, 1 suppose, that 

 the great and leading piimriples of the Huttonian theory are incoa- 

 trovertible poiiits, and that it only fails in accounting for some 

 compaiatively unimjxjrtant phenomena. Surely a man of Mr. 

 Allan's profieiency in mineraiogical science cannot but know that 

 the very first principles of that hypothesis are controvertible points, 

 and have been, not only controverted, but in the opinion of per- 

 haps nine-tenths of the mineralogists of Europe, (v\l>atever they be 

 in his) proved to be false. A philosopher, like Mr. Allan's master, 

 «hould have known the rules of philosopliizing, and Mr. Allan 

 himself knows very well that two of these rules are, — fiist, to be 

 certain that the cause we assign exists ; — and secondly, that if it do 

 exist, it is suffieient to explain the phenomena we ascribe to it. 

 The Huttonian hypothesis is deficient in both these respects. Mr. 

 Allan might have spared himself the pains of the common-place 

 observations he makes about " descanting solely on weaker neigh- 

 bours," acute arguments of the critic," and " fair and candid dis,. 

 cussion." If he means to say that 1 have descanted solely on the 

 weaker neighbours of his incontrovertible points, 1 can with truth 

 return him the compliment, if 1 set him the exainble of such 

 conduct he has most faithfully copied it; with this ditierence only, 

 that after all his descanting on what he may conceive to be my 

 weaker arguments, he has not been able to refute a single one of 

 them. 



With respect to the comparison instituted by me betwixt Hut- 

 ton and Werner, which Mr. Allan says " was quite uncalled for," 

 I beg leave to differ from him in opinion. 1 think it was called 

 for, and my reason is this. — Mr. Allan had objected to the sy!?tem 

 of Werner, (among otiicr things no doubt) " that he had drawn 

 conclusions more general than were warranted by the circum- 

 scribed field to which he was confined. Now it appeared to me to 

 be a fit reply to Mr. Allan, an urgumtnttnn ad rtriiimdit.nit at 

 least, which should have imposed silence upon iiim, to shew bim 

 that the founder of his own system was liable to the same objection 

 which he brought against the founder of mine, and even in a 



