ANNIVEKSAEY ADDEESS OF TKE PEESIDENT. XXIX 



illustrated. If we might have monographs on a similar plan of 

 completeness embracing other ^reat divisions of our geological 

 system, each the work of the man most prepared for the task, 

 geology could never again appear other than it is — a firm and co- 

 herent structure of truths reared on an ample and adequate basis of 

 observed facts. One of the most acceptable parts of this very com- 

 plete work is the excellent table of the geological distribution of 

 the Silurian species of fossils, drawn up with minute accuracy by 

 Mr. Salter. 



In like manner I must call attention to the admirable volumes, 

 with maps and sections, by Prof. H. D. Eogers, which display, on a 

 scale of splendour worthy of so great a State, the geology of Penn- 

 sylvania. If we consider the date when this great undertaking 

 began (in 1836), and the toils and difficulties through which our 

 distinguished friend and feUow-labourer has won his way. to the 

 magnificent result which has been placed this day before us, our 

 congratulations at this happy completion of so great a work will be 

 mixed with cheerful hope that hereafter the sheets of our own 

 SuiTcy may be as fully illustrated by contemporaneous descriptions 

 of rocks and fossils, and phaenomena observed in the field. The good 

 examples set in this particular by Portlock and De la Beche have been, 

 indeed, in some respects carried out by special memoirs in illustra- 

 tion of some parts of England and "Wales ; and the Director-General 

 of the Survey has taken so much interest in this subject, that I hope 

 it may be found practicable to obtain authentic notices of every 

 sheet of the Survey of several districts formerly surveyed^ mapped, 

 and illustrated by sections ; for we are still in want of those de- 

 scriptive pages which might have been issued with the sheets and 

 the sections, but can never be well supplied by memory or recovered 

 from note-books, after the lapse of years and the pressure of other 

 engagements. 



Ireland, rich in the minerals which accompany the plutonic and 

 metamorphic rocks of its romantic coasts — rich also in the excellent 

 map of Sir E. Griffith, — has of late years added to active palteontolo- 

 gical research a revived attention to mineralogy. The zeolitic pro- 

 ducts of Antrim have engaged the attention of Andrews and Ap- 

 john*. Haughton and Galbraith have examined the felspars and 

 micas in the granites of "Wicklow f ; and Gages has been engaged in 

 tracing the exact progress of metamorphism in several cases where 

 it was little expected, by methods not less ingenious J than those 

 employed by Mr. Sorby in scrutinizing the gas- and water- cavities 

 in the constituents of many rocks §. 



In Scotland, the recently published map of Prof. Nicol, with the 

 compendious note on Scottish Geology which accompanies it, wiU be 

 found of great service in the stiU unanswered questions suggested 

 by its strongly-marked physical features, its amazing areas of meta- 



* Reports of Brit. Association, Proc. Geol. Soc. of Dublin, &c. 

 t Phil. Mag. and Annals, passim. 

 \ Reports of Brit. Association, 1858. 

 § Quart. JouTD. Gepl. Soc., 1858. 



