NA TURE 



6<r 



THURSDAY, NOVEMBER 28, 1878 



RAMSAY'S MANUAL OF BRITISH GEOLOGY 



The Physical Geology and Geography of Great Britain : 

 A Manual of British Geology. By A. C. Ramsay, 

 LL.D., F.R.S., &c., Director-General of the Geological 

 Surveys of the United Kingdom. Fifth Edition. (Lon- 

 don : Ed\vard Stanford, 1878.) 

 THIS well-known -work has now reached its fifth 

 edition, and has undergone such changes that it 

 may be almost regarded as a new book. Not only has 

 the quantity of matter in it been almost doubled since 

 the last edition, and its bulk and price augmented in 

 the same proportion, but its plan has been very greatly 

 modified, as is indeed indicated by the second title now 

 prefixed to it. 



The original work was justly deserving of the very 

 great success which it achieved. It consisted of a cor- 

 rected report of one of the well-known series of lectures 

 to working-men delivered by the author in his capacity 

 of Professor of Geology in the Royal School of Mines, 

 at the Museum in Jermyn Street ; and it was a model of 

 clear exposition of a branch of science by one who was a 

 master of his subject, and who at the same time had 

 acquired great experience and skill in presenting it to 

 popular audiences. Probably no better introduction to 

 the principles of geology could possibly be recommended 

 to the English reader than this little book of Prof. 

 Ramsay's. 



We must confess to feeling that this complete re- 

 modelling of the plan of a work that has already proved 

 so successful, is a somewhat hazardous experiment. The 

 original chapters of the book, which still retain the cha- 

 racteristics of popular lectures, do not always harmonise 

 in style with the portions that were primarily intended 

 for the pages of an encyclopecdia. Indeed, as is admitted 

 in the preface, the book now consists of two distinct 

 works fused into one, and the reader is again and again 

 reminded of the fact by somewhat awkward transitions 

 and by abrupt changes in style and in the mode of treat- 

 ment of ihe subject. 



In almost every other respect we find the work to be 

 worthy of the highest praise. The clearness and general 

 accuracy of the information imparted by the book are as 

 conspicuous in this as in the earlier editions, and Prof. 

 Ramsay amply prores that he has not lost the most im- 

 portant gift which a teacher can possess, that of com- 

 municating his earnestness and enthusiasm to his readers. 

 Many of the questions treated of at considerable length 

 are of a somewhat controversial character, and the author 

 has again and again to remark that he is teaching, not 

 the universally accepted facts of the science, but the 

 views which he himself has been led after long and care- 

 ful study to adopt, and which he is sanguine enough to 

 believe will be eventually accepted by all his brother 

 geologists. Prof. Ramsay has certainly the merit of never 

 being uncertain or hesitating in his convictions, and those 

 who differ from, equally with those who coincide in opinion 

 Vi-ith him, will be glad to have the opportunity of reading 

 his latest and most perfectly matured deliverances on ques- 

 tions in the discussions upon which he has long taken a 

 Vol, XIX.— No. 474 



very prominent part. We are bound to say that in respect 

 to these matters he writes with the most perfect candour, 

 and is ever ready to admit that there are subjects in which 

 the timidity or caution of other geologists does not permit 

 them to follow him in his bold generalisations. 



The space at our disposal will not permit of our enter- 

 ing into detail on the numerous interesting questions 

 suggested by a perusal of this took. The author's 

 attempts to picture to the mind of his readers the 

 ancient physical geography of our portion of the globe 

 during successive geological periods may be cited as 

 among the most graphic pieces of writing, and at the 

 same time the most valuable portions of the work. Here 

 Prof. Ramsay is CNndently entirely in his element ; he 

 wxites with an enthusiasm which is perfectly contagious^ 

 and his arguments, if not always sufficient to carry con- 

 viction, are at all times worthy of serious consideration. 



We cannot resist quoting Prof. Ramsay's latest views 

 on the important and_much-vexed question of the classi- 

 fication of the Cambrian and Silurian rocks. On this 

 subject he remarks : — 



" If these strata were to be classified for the first time 

 in England, with my present knowledge, I would divide 

 them into three, as the most convenient method. The first 

 series would include the purple and green grits and slates 

 of the Longw>'nd and Wales, and range upwards as high 

 as the top of the Tremadoc slates ; the second would 

 range from the base of the Arenig slates to the top of the 

 Bala or Caradoc beds ; and the third from the base of 

 the Upper Llandovery beds to the top of the Ludlow 

 rocks.' ' 



It is true that after this statement, which is in such 

 perfect harmony with the results arrived at by palaeonto- 

 logists in Bohemia, Scandinavia, America, and our own 

 country, Prof. Ramsay announces his intention of still 

 adopting the nomenclature of Murchison and the Geo- 

 logical Survey, which he admits to be " old-fashioned ; " 

 but he states that his reason for doing so is simply 

 that this plan will be the most convenient for those 

 who wish to consult the geological maps and sec- 

 tions published by the Government. As the date fixed 

 for the completion of the Government Survey is now 

 passed, we may perhaps hope that the Director-General' 

 will be able to devote his attention to the much-needed 

 reform of that old-fashioned classification and nomen- 

 clature. At all events, every geologist will be gratified 

 by learning from so high an authority that any difference 

 which may now exist concerning the classification of the 

 older palaeozoic rocks is mainly one as to the employ- 

 ment of certain terms, and that on the actual facts of 

 the case something like substantial agreement has at 

 last been arrived at. 



On another question, that of the date of the earliest 

 traces of human workmanship in this country. Prof. 

 Ramsay's remarks are certainly not calculated to give 

 quite so much satisfaction to his readers. He writes : — 

 " The antiquity of man being thus clearly established, it 

 becomes obvious that his advent into our area was either 

 of pre-glacial or of inter-glacial date. I say inter- 

 glacial, because Mr. Skertchly has lately discovered 

 palaeolithic flint implements in certain brick-earths. 

 Similar, and I believe identical, brick-earths underlie the 

 * chalky boulder-clay ' in the neighbourhood, the boulder- 

 clay having been removed by denudation from that 



