226 Correspondence. 



interesting results obtained during the progiess of the Survey are 

 here described," 



In my communication, I based my remarks upon principles which 

 the entire geological world will unanimously concede to me, viz : — 

 That in an investigation of admittedly one of the most intricate and 

 abstruse problems which form the subject of geological research, it 

 is absolutely, nay, vitally, essential that each step forward in the 

 inquiry should be tested with the utmost care and suspicion ; that 

 each argument, derived from the collateral sciences, should be 

 thoroughly examined into, as to soundness ; and that no misunder- 

 standing should be allowed to arise from the use of a bad or 

 indefinite terminology. 



From the tenor of Mr. James Geikie's remarks, may it not faii-ly 

 be asked : — To whom does he address himself ? or, for whom is 

 he writing? whether to beginners in the science, or to the Geo- 

 logical Society of London ? If to the former, may it not be inquired, 

 whether the subject is not, in itself, too abstruse for beginners, and 

 should not the most scrupulous care be taken, that nought but 

 admittedly sound arguments, nomenclature, or similes, be made use 

 of ; for all know how exceedingly difficult it is to eradicate incorrect 

 notions, when once they get into the head of a beginner in science. 

 If to the latter, to whom his first memoir is especially addressed, 

 are not geologists, when an author ventures to bring novel and 

 sweeping* views in the most abstruse departments of the science 

 before a tribunal supposed to represent the highest geological talent 

 of the empire, fairly entitled to demand that, at least, his premises 

 are not indefinite or unsound, and that his phraseology is not, as 

 admitted, " careless and unguarded." 



After a careful perusal of Mr. James Geikie's reply, I cannot find 

 anything therein which in any way disproves, or even shakes, the 

 weight of my arguments ; but, from that gentleman's defence, I can 

 clearly understand, that the time has come when it will not do to 

 mince matters in this discussion ; for, as the reader will perceive, it 

 is not against Mr. James Geikie that I am fighting, but against the 

 system which he now attempts to defend. 



Glad should I be if I could (as Mr. James Geikie would charge 

 me with) believe " that the terminology of petrology is as fixed as 

 that of the exact sciences ; " what I do, however, believe is, that it 

 ought so to he, and further, that it is a disgrace to the present state of 

 geological science that it is not so. 



No person is more fully aware that " looseness " in petrological 

 nomenclature is unfortunately the rule, not the exception ; and that 

 geologists may continually be found mapping and writing of totally 

 different rocks, under one and the same name ; what I, however, 

 would infer therefrom is, simply, that it is high time to reform. 



In what, now, does Mr. James Geikie's defence consist ? Upon 

 perusal of his reply, it will at once be perceived that it is, in major 

 part, a simple "tuquoque" to other (often eminent) writers upon 

 the subject; an argument which vany be very effective against these 

 gentlemen, but one which the rest of the geological world will not 



