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consist of blue clay slate, not differing, in | he can do that, however, he must learn to any essential character as a kind of rock, recognise the general characters of the from the slates found in the old Palæozoic groups of fossils, and as many of the characrocks of our part of the world. These terms teristic species as he can. The formations then necessarily lose all their original litho- of any period will consist of different kinds logical significance, and are to be under- of stratified rocks in different localities, stood in a chronological sense. In speak- and may consist of any kind whatever, or ing of Cretaceous rocks, we mean merely may be associated with any description of rocks that were consolidated in that great igneous rocks; while they can only conperiod during a part of which the chalk oftain the remains of such animals and plants Europe was formed, and so of all other as lived during the time when they were similar terms.
deposited. The process is this : geologists first of The learner must also recollect that any all examine some part of the earth's crust given area may have been an area of dewhich exposes a great series of stratified struction during one period, an area of prorocks,--they observe the rock groups of duction during another, or what we have which this series consists, and the fossils called an area of neutrality during a third. which each of these groups contains. They In any particular place therefore the series find that the fossils of one group of rocks of stratified rocks may
very defective, differ from those of another, and that the rocks of period 8 or 10 resting on those there is a series of groups of peculiar fos- of 2 or 5; but it is quite impossible, from sils coincident with the groups of rocks. the nature of the case, that the order of The mere varieties of rock, however, are the series can be ever inverted. found to be comparatively few, and are apt Is there any fevered student or overto recur in the different groups. More worked man of business in the seething over, each group is apt to vary when fol. caldron of London life, who wishes for lowed from one place to another. The some pursuit that shall impart a new di. fossils, on the other hand, always remain rection to his hard-strained thoughts, and the same in each group, and none of them give healthy exercise to his toil-worn frame, ever recur in the different groups. In ex- let him peruse in the stony records themamining any detached bed of rock, there- selves the history we have been recountfore, the fossils are a better guide than the ing. He has only to furnish himself with nature of the rock. The determination of a good geological map, a hammer, a stout the order of the groups of fossils is in the pair of walking boots, and a knapsack, and first instance based upon their discovery either walk, ride, or drive about the counin the series of rocks; but when that order try with his eyes open. He must take note has been established, and when it has been of all the quarries and cuttings he may see, tested by its application to many different and mark the external features of the parts of the earth's surface, and found to country he traverses, connecting them be invariable, then it is accepted as a guide with the internal structure which he disin the classification of the rocks of other covers here and there at intervals. He parts of the earth's crust, where the order will then find that the whole structure of of the series of rock-groups would not be the country, and all the wonderful history otherwise discoverable.
of the first formation of the rocks, and the The beginner in Geology will find his occurrences that have since befallen them, progress greatly facilitated if he keep will insensibly be unfolded before bim and steadily in view that the classification and gradually grow up in his mind. If once nomenclature of the stratified rocks is he get hold of the clue, and make one or fundamentally chronological. When once
When once two steps in the investigation, his attenhe knows how to recognise limestone, tion will be arrested, his interest excited, sandstone, and clay, and their more ordi- and he will feel like one just entering into nary varieties, he knows all the varieties of the plot of some well-told story, eager to stratified rocks, so far as the nature of the know more. Every quarry, every cutting, rock is concerned. If he learns to dis- almost every stone by the way-side will be tinguish granite, syenite, greenstone, fel- anxiously scanned for additional facts, stone, basalt, and scoriaceous lava, he every hill side breasted, and every dingle knows all he need know of the igneous or penetrated. The Book of Nature too has unstratified rocks. Beyond that he need this advantage over the stories composed not trouble himself with rocks and their by men, that it has no end, and its interest varieties, until he has made considerable grows with every fresh perusal. To read progress in the science, and is prepared to it we must breathe the free air and live go more minutely into the subject. Before for a time in the open field, with not only the mind amused, but with the muscles in- done, and the great practical value and vigorated, the nerves braced, and the utility that would be obtained if surveys, blood coursing through the veins with that still more detailed, and on a systematic pleasurable glow that makes every breath plan, were to be undertaken. This could we draw a pleasure in itself-while good only be accomplished at the public exdigestion waits on appetite, and health on pense. Some of the European Governboth.'
ments, and, still earlier, some of the As regards maps, the novice in this United States of America, ever foremost country will find the guide he requires in in works of practical utility, established the beautiful map of England and Wales, state or government surveys: some of our by Protessor Ramsay, which contains, in own colonies followed the example, and a condensed form, the result of the labours at last the British Government, at the inof many men, continued through half a stance of Sir H. T. De la Beche (and after century. It has all the latest discoveries, he had commenced the work at his own is excellently coloured, and of a scale just labour and cost), founded a Geological large enough to be distinct. The smaller Survey, which has since grown into an inmap, by Sir R. I. Murchison, is equally stitution, which appears likely to become good in execution, but from its smaller permanent. Since then Canada, India, scale not quite so serviceable as that of Australia, the Cape of Good Hope, and Professor Ramsay. For a glance over the other places, have commenced or extended structure of Scotland, we may take as our their geological surveys, chiefly under offiguide the very useful map published by cers trained in the school of the mother Professor Nicol. Excellent as it is, how country. ever, it has to our eyes some drawback in The Geological Survey of the United its colouring, since he makes the Old Red Kingdom is conducted under the powers Sandstone of Scotland a pale dirty green, of an Act of Parliament passed in the 8th and indicates the Coal-measures by a and 9th year of Victoria (1845). Sir II. minute cross-hatching, which it is torture T. De la Beche, the first Director-General, to the eye to look through in search of was succeeded by Sir R. I. Murchison in the names, and which is moreover scarcely 1855. It is divided into two branchesdistinguishable, either in colour or chå- the survey of Great Britain, under the racter, from that employed to indicate local directorship of Professor A. C. RamChlorite slate. The geology of Ireland say, and that of Ireland, now under Mr.J. has been most admirably delineated so far Beete Jukes. In Ireland and in those as the labour of one man, with but little parts of Great Britain which have been assistance, could accomplish such a vast laid down on the scale of six inches to the work, by the maps of Sir Richard Griffith. mile, the field observations are inserted in The last edition of his large map will be the maps, while the results are published an enduring monument to his name; by means of geologically-coloured copies and a small and cheap edition which hé of the maps on the scale of one inch* to a has published is well adapted to give a mile, accompanied by printed explanations general notion of the structure of Ireland. and memoirs. The amount of labour ex
Maps of sufficient accuracy to enable us pended on these works can only be rightly to give even a slight outline of the struc- understood by the field geologist. If any ture of the British Islands, were the result one wishes to put it to the test, we recomof the labours of many men for many mend him to take one of the maps of years. M'Culloch laid the foundation in North Wales, and try, among the rugged Scotland; Weaver and Portlock, and precipices of Cader Idris or Snowdonia, t others, had laboured in Ireland both before Griffith and contemporaneously with
* We believe that some of the districts of the him. Greenhough, in England, had
north of England and of Scotland will shortly be bined with his own explorations the re-coloured, and that two sheets of the one-inch map
published on the six inch scale, geologically sults of those made by W. Smith, Fitton, of Scotland are nearly ready for issue. Cony beare, Buckland, De la Beche, Phil- + The only man capable from his own knowlips, Sedgwick, Murchison, and many Wales was Professor Sedgwick.
ledge of forming a judgment on the maps of North
He had, unasSimilar maps, more or less com- sisted, except by his own inexhaustible bodily enplete, had been published abroad by ergies, keen perceptive faculties, and sagacious equally enthusiastic cultivators of the grasp of intellect, unravelled all the intricacies of science. Still it was felt that this was not the mountainous districts of North Wales and the enough. The maps and the descriptive
Lakes (to say nothing of other regions), and had memoirs thus put forth by individuals, or
in his mind as perfect a model of those countries
as could be constructed by any surveyors. In by societies, only showed what might be North Wales indeed he was in some of his conclu
to trace out by its guidance the complica- work requiring a combined action, each tion of intrusive and contemporaneous man must be confined within a certain disigneous rocks, and their associated ashes' trict until he has completed its examinaor 'tuffs,' variously interstratified with tion, and carefully recorded everything different kinds of aqueous rocks, and to that is to be seen in it; while there are follow these multiform and often irregular other problems which can be solved only structures through all the complex intri- by rapid motion over a whole region, or cacies of flexure and contortion, fracture even regions, for the purpose of examinand dislocation, into which subsequent ing widely-separated points, and compardisturbances have thrown them, and over ing quickly the rocks and fossils of differall the abrupt declivities of mountain, val- ent countries, so as to bring into one view ley, and ravine, which subsequent denuda- the scattered facts belonging to one class tion has worn in them. Or if he has not of objects. nerves and sinews for such a task as this, This individual research is necessary let him take one of the maps of a lead or even for descriptive geology itself, and copper mining district, and examine the gives a special value to such books as Sir net-work of gold lines that represent the R. I. Murchison’s ‘Siluria, of which we mineral veins; or a map of a coal district, have now to hail, with pleasure, the apand study the convoluted black lines that pearance of a third edition. We expressed mark the out-crops of the various beds of our opinion of the excellence of this work coal, and the numerous white lines that when it first appeared, and its supreme cut across them and represent the faults importance to geologists who were enwhich dislocate them, and he will begin to gaged in investigating the Palæozoic, and acquire some notion of the labour, and especially the Lower Palæozoic rocks. patience, of which the colours and marks The improvements introduced in the last on the maps are the external signs. What- edition have almost made it a new work. ever errors of detail may here and there In addition to the results of his own perexist in the earlier sheets, either of Great sonal investigations, Sir Roderick bas now Britain or Ireland, will, doubtless, disap- supplied an abstract of the most recent pear hereafter, when the enlarged expe- labours of the Geological Survey, together rience acquired in the progress of the task with information gathered from almost can be brought to bear on their revision. every quarter of the globe. He has himSuch a work as this, indeed, is almost end- selfre-examined his native Scotland. The less. Even could we look forward to the latest work of Ramsay, Aveline, and Salcompletion of a Geological Survey in the ter, in Wales, appears in it, as well as the most perfect manner possible, there would newest information on Ireland. Professor still be need for an establishment in which Ramsay has contributed a condensed to preserve the vast mass of records that classification of the Palæozoic rocks of will have been accumulated, and of prac- America; Messrs. Salter and Morris a tised officers familiar with them, ready to most valuable catalogue of Lower Palæogire to every applicant the precise piece zoic fossils; Mr. A. R. C. Selwyn has of information he requires.
given very interesting matter from AusNecessary, however, and inevitable as tralia ; Sir W. Logan from Canada, and we consider Government Geological Sur- many of the first authorities from differveys, they will never supersede individual ent parts of the continent and other quarinvestigation. Their especial duty is to ters of the globe. The mass of matter accumulate data that it would be impossi- contained in this book is, indeed, so enorble for individuals to procure, in conse- mous, that it would be impossible for us quence of the great time required to be here to give an idea of it. It requires expended on them. There are many pro- close study on the part of a professed blems, both in geological physics and in geologist, and must then remain with him palæontology, of which it is no part of a as a book of reference for constant use. Government Survey even to undertake the Sir R. I. Murchison is a singular ininvestigation. It is obvious that, in a stance of a man who, having passed the
early part of his life as a soldier, never sions, more accurate than the first work of the having had the advantage, or disadvansurvey, All geologists must ever regret that the tage as the case might have been, of a failing health of subsequent years has prevented scientific training, instead of remaining a this hvaš dvigcv from doing that justice to his ear- fox-hunting country-gentleman, has sucno geologist can forget him as one of the’ablest ceeded by his own native vigour and pioneers of the science, as well as its most elo- sagacity, untiring industry and zeal, in quent and spirit-stirring expounder.
making for himself a scientific reputation
that is as wide as it is likely to be lasting. I loured in this beautiful fashion, and their He took first of all an unexplored and dif- cost reduced at the same time that their ficult district at home, and, by the labour value would be increased ? The best of many years, examined its rock-forma specimen of a chromo-lithograph map tions, classed them in natural groups, as- published in Britain is that of Yorkshire signed to each its characteristic assem- by Professor Phillips—a most excellent blage of fossils, and was the first to deci- pocket map for any one who wishes to expher two great chapters in the world's plore the geology of that interesting geological history, which must always county. henceforth carry his name on their title- The little map of a small part of Swepage. Not only so, but he applied the den, round the neighbourhood of Upsala, knowledge thus acquired to the dissection by Mr. Axel Erdmann, is remarkable, beof large districts, both at home and abroad, cause, unlike most other geological maps, so as to become the geological discoverer it delineates not only the solid rocks, but of great countries which had previously all the different matters that occur bebeen terræ incognita.'
tween the upper surface of those rocks With such a training he was well en- and the actual vegetable soil; so that we titled to publish the Geological Map of see the areas occupied not merely by Europe, which he put forth some time ago peat, but by moss not yet converted in conjunction with Professor Nicol. Af into peat,' by ' shell marl," infusoria clay,' ter the appearance of the beautiful Geolo- alluvium, • black fucus marl," "stratified gical Map of Russia, which accompanied clay,' 'fir-tree sand (as it is called), 'anhis second great work (that on Russia gular gravel, and rolled gravel, the and the Ural Mountains), he had enclosed solid rocks rising only here and there like Europe, as it were, on two sides, in a islands through these various superficial frame of his own handiwork. He had, deposits. Such information must be most moreover, harmonised the work of many valuable to the agriculturist, and it will other observers and combined it with his remain for the Geological Survey of the own, with respect to more recent forma- United Kingdom to undertake the contions in the centre and south of Europe, struction of similar maps of the superficial in his paper on the structure of the Alps, deposits after the record of the formations Apennines, and Carpathians, published in beneath them has been completed. the Journal of the Geological Society.' Of the United States of America and His map bears the date of 1856; the the British American colonies the most other map of Europe, which we have recent results are contained in Sir W. Lomentioned in the list at the head of this gan's “Reports on the Survey of Canada article, is, unfortunately, without a date. for the years 1853 to 1856,' and Professor It was compiled by the late M. Dumont, Rogers's Geology of Pennsylvania. The the excellent geologist of Belgium. In the method to be pursued in a partly-uninhagreat outlines the two maps agree, as must bited country, of which no complete toponecessarily be the case if they be correct; graphical map exists, must necessarily be in portions of the details there are differ- very different from that adopted in older ences, and in some of these the English lands, fully opened by roads and accuwork is, we think, the more correct of the rately delineated. Sir W. Logan has actwo. The Belgian map, however, is on a cordingly been compelled in many cases to rather larger scale, and in many places is contine his observations to the borders of more minute; while, as to the beauty, dis- rivers and lakes, where alone they could tinctness, and permanence of the colour- be made with accuracy and their locality ing, the map of Dumont not only excels precisely determined, while he has as yet that of Sir R. I. Murchison, but is, beyond been unable to construct a general map of all comparison, the best coloured map we sufficient correctness to receive his obserever remember to have seen. The vari- vations, though one is said to be in proous colours are so clear and sharp, that no cess of completion. The reports, however, overlapping can be detected, even by the contain many detached remarks of value lens when applied to dots not larger than to the geologist, and teach him what to a pin's point, or to small spaces having the expect when the remainder shall be pubmost sinuous and deeply-indented outlines. lished. Why is it that equally good lithographic Professor Rogers's 'Geology of Penncolouring is not produced in Britain, and sylvania' is a most remarkable work. applied to our own maps? why, above all, is called a Government Survey, and it was should not the maps of the Geological commenced and partly carried on under Survey-a great national work-be co- the auspices of the State, and at the public
expense. Owing to the vacillation, how-| tical as well as literary side, how impossiever, which too often characterises assemble he finds it to master both! If he buries blies of men ignorant alike of the theore- himself in a library or museum, surrounded tical value and the practical importance of by books, maps, papers, and specimens, scientific research, the funds were more bow often he longs to examine facts for than once withdrawn from the under himself in the field,' and finds time, and taking, and Professor Rogers was at last distance, and money alike difficulties in his compelled to complete it chiefly at his own path! If, on the other hand, he be a field expense. Maps, sections, drawings, dia- workman, how deficient be often finds grams, and figures of fossils
, besides de himself in the knowledge of what others scriptions of countries and rocks enough have recorded in books! The very sight to fill three great quarto volumes of letter- of a thick quarto is enough to appal any press, are all the work of Professors H. D. one who has but snatches of time at his and W. Rogers. When we reflect that disposal. Geological works become so they had to deal with a country containing numerous, that even professed geologists about 44,000 square miles (or only about must need despair of reading them all; 6000 less than England and Wales), tra- therefore we would, above all things, beversed by a complicated mountain range, seech geological writers to study condencomposed of a very varied series of rocks, sation. Doubtless, each may say with thrown into a wonderfully complex form, Horace, Brevis esse laboro, obscurus fio,' we shall be able in some degree to appre- but we do not mean so much brevity of ciate the amount of their labours; espe- expression as selection of matter. Minute cially when we also remember that, like details are in many cases necessary for Sir W. Logan, they had often to make those who may wish to follow the writer their own maps of the surface before they in all his steps, but those persons must be could even commence their more proper few compared with the increasing number labours of representing upon them the of such as wish merely to grasp the leading boundaries of the rocks below. It is truly points, and to acquire a general notion of a noble work, and will form an enduring the country, rocks, and fossils. It will be monument to the ability, as well as to the for the interest then, we think, of future perseverance and public spirit of the au- geologists to make a careful abstract of thors. The sole objection we have to their observations, whether for the use of make is to that fantastic nomenclature men of science or ordinary inquirers, and which no person, we think, except Profes- keep distinct the details which may be sor Rogers, will ever dream of adopting. necessary for the few. This opinion has We hope that he will take the earliest op been forced upon us while examining the portunity of laying aside a 'façon de par- books enumerated at the head of this artiler of which the result is to render himselt cle; and we have often felt inclined to partially unintelligible to the geologists of paraphrase St. Augustine's exclamation on the rest of the world, and to throw around Persius, and say “Si non vis legi, non him a barrier of isolation which separates potes intelligi.' him from his brethren of the hammer.
The reports hitherto received from the Geological Survey of India have been brief and detached; but this may well be excused, when we consider the size of the country to be examined and the circum- ART. VI.-1. Journal of a Cruise among stances under which it has been lately the Islands of the Western Pacific, inplaced. The surveys of the Australian cluding the Ferjees, and others inhabited colonies, especially that of Victoria, under by the Polynesian Negro Races, in Mr. Selwyn, have already been fruitful in H.M.S. Havannah.' By John Elphin- . results of the highest interest to the man stone Erskine, Capt. R.N. London, of science, and of daily-increasing value to 1853. the inhabitants of the countries examined. 2. Fiji, and the Fijians : the Islands, their Tasmania is about to be surveyed by a Inhabitants, and Mission History By young geologist, the son of the eminent
Thomas Williams and James Calcraft, ornithologist, Mr. Gould.
late Missionaries in Fiji. London, 1858. Ars longa, vita brevis est :- Who is 3. Lettre concernant l'Etat actuel de Tahiti, there that takes up any pursuit in earnest adressée à Sa Majesté Impériale Napo. who has not this aphorism always recur- léon III. Par Alexander Salmon. Lonring to his thoughts? If he is engaged in don, 1858. a science which, like geology, has its prac- 4. La Nouvelle-Calédonia ; Voyages, Mis