;86 



NA TURE 



[February 21, 1895 



his own favourite expressions. He rapidly took in the 

 lie and relation to one another of the rock masses. To 

 this any geologist who has worked with him in the field 

 can testify, and this is what lends its value to his classical 

 memoir on the geology of North Wales, and to the 

 maps and sections of which it is explanatory. But when 

 he had sketched out the outlines of the history of the 

 ancient volcanoes of that area, and had noted the choked 

 craters now exposed by the denudation of the overlying 

 masses of lava and cinder and mud, and when he had 

 described the isolated portions of the volcanic and marine 

 deposits which, building up mountains round the ancient 

 roots of the volcano, still remained the record of great 

 sheets that once spread continuously far and wide over 

 the whole area ; when he had done all this, he turned 

 to another aspect of the question, and sought a clear 

 answer to the inquiry how much rock, which we know 

 surely once covered this area, has been removed by 

 denudation .' and we find in the same memoir sections 

 illustrating the conclusions at which he had arrived. 



For when " he had traced out the structure of a com- 

 plicated geological region, and was able to show what 

 should have been the form of the surface had it depended 

 on geological structure," he was then ''in a position to 

 demonstra'e how much material had been removed by 

 denudation," namely, all that was above what he called 

 the Plain of Marine Denudation, that is the old base 

 level of ancient erosion, down to which all the agents of 

 waste — rain, rivers, ice, and sea — had reduced the up- 

 lifted land ; or perhaps, as we should now say, giving 

 greater prominence to subacrial action, to the level at 

 which the sea had arrested the work of the various 

 agents that were reducing all dry lands to sea level.. 



Few men's work illustrates better than Ramsay's the 

 place and value of a good " working hypothesis " in some 

 kinds of higher scientific research. Imaginative and 

 fertile in suggestion, no one was more sorry when 

 further observations did not clearly support his first 

 impressions, and he tried and tried and tried again to 

 make it fit ; yet he bowed always with deference to 

 established evidence and logical consequence. 



Besides his regular survey work, which was itself full 

 of new observations and original treatment, and besides 

 many papers giving the results of his researches on 

 special points, he from time to time plunged into more 

 speculative questions, and advanced some theory in 

 explanation of the larger phenomena, especially those 

 connected with surface configuration. For instance, 

 reflecting on the great quantity of fine mud, " flour of 

 rock," carried down by glaciers, and observing that ice 

 was not, like water, restricted in its flow to continuous 

 downward slopes, and holding that ice charged with 

 stones would grind away more rock where the pressure 

 was greater or the rock softer, he propounded the theory 

 of the glacial erosion of rock basms. 



Ills explanation is probably true in some cases, but he 

 gave it a wider application than has been borne out by 

 subsequent investigations. 



Unfortunately he adduced as his first example the 

 Lake of Geneva, a basin to which even those who agree 

 with him upon the general probability of there being 

 glacially eroded hollows such as his theory requires, 

 would not now be prepared to apply it. 

 NO. I 32 I, VOL. 51] 



The public will read with profit and pleasure the 

 biography of such a striking personality by a graceful 

 and accomplished writer, who knew all about the man 

 and his work, and had the skill to select with judgment 

 and the good sense to keep the whole within the modest 

 bounds of one volume of large print. Ramsay's many 

 friends will love to have the record of his struggles and 

 his triumphs, so many of which are told in his own words. 

 Every survey man, not only of Great Britain, but through- 

 out the world, will turn to this account of the commence- 

 ment and growth of the geological survey of Great 

 Britain, and cannot fail to profit by the insight it gives 

 into the methods, life, difficulties, and results of that 

 important branch of the public service. 



So easily does the story run, that we cannot say 

 whether the general reader, or the scientific student, will 

 be-t appreciate this sketch of the progress of geological 

 research through the most active and interesting half- 

 century of its history. 



OUR BOOK SHELF. 



Harvard College by an Oxonian. By George Birkbeck 

 Hill, D.C.L. (London : Macmillan and Co., 1S94.) 



Dr. BiRKliECK Hill spent two months in 1893 in 

 Cambridge, Massachusetts, and has compiled this little 

 volume giving some account of the history of the cele- 

 brated college and university of Harvard. So far as 

 Dr. Hill rclie> upon previous publications, his account is 

 accurate, but his own observations and impressions are 

 — as is very natural — ofien quite erroneous. Scant 

 justice is done to the import.Tnt and costly arrangements 

 for the study of the various branches of the natural 

 sciences which exist either at or in connection with the 

 Massachusetts university. Dr. Hill is not fitted by his 

 own education and experience to report on these matters, 

 nor, indeed, can much value be attached to his some- 

 what antiquated standpoint as a critic or observer 

 of university institutions. He contrasts Oxford and 

 Harvard at every step, but he fails to give any picture or 

 presentation of the real characteristics of the student's 

 life at Harvard. He does not sufficiently emphasise the 

 fact that the undergraduate at Harvard enjoys the im- 

 mense benefit of true university education, at the hands 

 of distinguished professors, with freedom and inde- 

 pendence in regard to his choice and meihod of study, 

 and as to such personal details of life as board and 

 lodging ; whereas the Oxford undergraduate is treated 

 throughout his career as a goose to be nursed, monopo- 

 li^ed and plucked by college ushers, who (owing to the 

 system under which they are appointed) arc, as a rule, as 

 little capable of good teaching as they are of managing 

 the domestic and disciplinary details of the college- 

 boarding-houses. Dr. Hill notes that the rage for 

 athletics is almost as serious an injury to study at 

 Harvard as it is at Oxford. L. 



Tableau MtHrique dc Logarithmes. By C. Dumesnil. 



rParis : Libralric Hachette and Co., 1S94.) 

 The use of logarithms for calculations is, as every one 

 knows, a great saving of labour and time, and what 

 otherwise would be complicated pieces of work are re- 

 duced to simple computations. The facility of woiking 

 depends, alter some time, on the good or bad arrange- 

 ment of the tables, but instances often occur where 

 much time is lost by having to turn pages backward 

 and forward. For the case of logarithms to five places 

 of decimals, M. Dumesnil has devised a means of 

 eliminating altogether the use of tables, by adopting a 

 series of scales neatly printed on stout sheets. From 



