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IN THE FIELD!
We have searched for plants, dredged for shell-fish, and, as the sneer goes, “ hunted for butterflies ;” but of all natural-history pursuits, that of geology is, to our mind, the most exhilarating and thought-inspiring. Botany and zoology have no doubt their charms and attractions, require much research and discrimination, and bring us in contact with some of the subtlest problems that can engage the human intellect; but they deal with the recent, and with a phase of the world which at best is but temporary and external. Geology, on the other hand, deals with the internal as well as with the external, with the past as well as with the present; lifts the veil from the extinct, and marshals in chronological order the long line of events, physical and vital, which constitutes the history of our globe from the current hour back to the remotest ages. All physical change, all vital relationship, all continuity of law and of order, come within the range of its cognisance, requiring the minutest observation and the most exact and sequential reasoning. Even as a mere field exercise, geology has higher and more permanent allurements. Botany and zoology, however attractive their objects, are restricted in a great measure to certain seasons of the year, whereas
the objects of geology are ever patent—in the precipice, ravine, and sea-cliff; in the quarry, mine, and road-cutting -wherever there is a rock-surface exposed, or a section presented to investigation. Be it the exciteinent of searching for fossils, the bracing exertion of climbing over ledge and scaur, the deeper thought inspired by a survey of wild ravines and hoary mountain-heights, or the freer breathing and wider scope of the breezy upland, there is something ennobling in a geological field-day that we seek for in vain in any other pursuit. Even the ordinary objects of the public highway become invested with interest to the geologist unknown to other travellers, presenting fresh subjects for examination at every turn, and suggesting new problems for solution. Let us glance at some of these objects, and the new importance they assume when viewed from the stand-point of the working geologist.
Breakfasted, and off at eight on a fine summer morning with staff in hand, bag a-shoulder, and hammer and chisels in waist-belt, the young geologist is presented with a thousand objects beneath and around him that would pass unobserved by the ordinary excursionist. Out of, but scarcely beyond, the suburbs of the town, there is the stone-breaker busy at his heap of blocks and boulders gathered from the adjacent fields, or carted from the neighbouring sea-shore. A mere heap of road-metal ! True, but what a wonderful assemblage of rocks-quartzites, granites, porphyries, greenstones, felstones, and jaspers—enough to teach the whole science of lithology, or fill a cabinet with specimens of the primitive rock-systems ! And then, what wonderful incidents in world-history these despised blocks and boulders suggest! Wear and waste from far-off hills ; grinding and rounding by ages of attrition; transport by ice-sheet or iceberg in distant epochs, when this island of ours lay mantled in snow and ice, or, sunk beneath the ocean, received the drift of berg and floe as they melted away in the upper sunshine. Let no one who values the teachings of his science pass indifferently by the heap of road-metal, whether consisting of miscellaneous boulders from the fields, shingle from the sea-shore, greenstone from the hills, chert from the limestone scaur, or flint from the chalk-pit. Each has its own lesson fraught with information, or its problem to suggest. Nor let him despise the knowledge of the homely stone-breaker, or refuse to listen to his quaint questions and often quainter theories. There may be curious ideas simmering in that bonneted grey head; strange intelligence peering through the wire-gauze that shades those twinkling eyes of his. We have been led to a knowledge of some of the finest intersecting dykes of basalt, and some of the strangest varieties of chalk-flints we ever witnessed, by a friendly chat with an honest labourer as he took his simple meal by the dusty wayside. And what has been the luck of one may readily be the luck of all, if they will only exercise a little frankness and affability to secure it.
Onwards our young friend goes, and the road which would seem dull and monotonous to the uninitiated, presents to him objects of interest and instruction even in its very fences. These, for the most part, are built of the nearest and readiest material—here of sandstone, there of greenstone ; here of blocks trenched from the neighbouring fields, and there of limestone too impure to be reduced to quicklime. These road-fences form in general the best and readiest indices to the geology of a district, and he who notes them attentively is not only premonished of the rock-formations that lie around him, but sees also the manner in which they are affected by exposure to the weather. Often has the examination of a roadside wall led to the knowledge
of some peculiar mineral stratum ; and not unfrequently the weathering of their unhewn blocks has led to the discovery of some fossil structure which no other process could have so delicately displayed. What magnificent polyzoa, bleached and apparent as the network of the laundress, have we witnessed on an Ayrshire roadside ; what superb encrinites, relieved to the minutest ossicle, have been gathered from a Yorkshire stone-wall! Let the roadside fence along which the young geologist may travel, or on which he may seat himself to indulge in his meerschaum, never be passed without examination. It is sure to lead to a knowledge of the rocks and quarries of a district the while that the observation of its materials will help to beguile the tedium and monotony of the way.
Even where metal-heap and stone-wall may be insufficient to attract, or are altogether absent, there is always some superficial excavation by the way_field-drains, sand and gravel pits, clay-pits, and suchlike openings, which should never be passed without examination. We have seen outcrops of strata and junctions of formation laid bare by field-draining which could never have been otherwise exposed ; and was it not in the gravel-pits of the Somme that Boucher de Perthes first found evidence of the contemporaneity of man and the extinct mammalia ? But here comes the clay-pit—a miry affair at the best, and a capital test of the enthusiasm of amateur geologists; and down our young friend goes in search of boreal shells and star-fishes, remains of arctic birds, seals, and whales. And what a treasure often awaits him! A perfect cabinet of shells, barnacles, and star-fish within the space of a few yards, or it may be the skeleton of a seal or the first exhuming of the gigantic remains of a Northern whale. There is scarcely a clay-pit we have visited on the east coast, from the Humber to the Moray Firth; or on the west, from the Clyde to the Sol
way, but has yielded such remains, proving as clearly as it we had been witnesses of the event that these islands of ours were at a period comparatively recent in geology surrounded by boreal conditions such as now prevail along the coasts of Greenland, Spitzbergen, and northern Scandinavia. And thus the clay-pit, forbidding to the ordinary tourist, and far from attractive even to the labourer to whom it becomes a source of daily bread, presents allurements to the geologist which draw him for days and weeks to its interior, and make him quite at home where others see only dirt and discomfort. The delight in discovering a new shell, the pleasure of cutting out the skeleton of a seal, or the sensation experienced in watching the day-by-day uncovering of the gigantic bones of a whale in situ, are things that may be described to others but can be known and felt only by the working geologist. We speak from experience; and, disabled though we be, we would willingly go once more to Cupar-Muir to secure another seal, or to Stirling to watch the exhuming of another whale.*
Attractive, however, as may be the treasures of the claypit, our young friend has other objects before him, and he must not linger. On he goes, certainly not improved in appearance by his pokings among the clay, but all the more
* How a discovery of this kind sometimes strikes the non-geological mind may be told of Thackeray. When lecturing in Scotland, he happened to be at Cupar station on the afternoon I had exhumed my first seal from the brick-clay of Stratheden. As the men came on the platform carrying the mass of clay in which the skeleton was imbedded, one of them addressed me: “Ye'll be gaun to tak’ your banes in beside you!" a question which tickled the humour of the novelist, and he became quite facetious, firing joke after joke to the great amusement of some friends who had accompanied him to the station. As I explained to him how and where the skeleton was found, his manner changed in an instant,“So this beautiful valley,” he inquired, “has been once an arm of the sea; not Noah nor Deucalion ? Quite clear ! but how many ages ago ?" And thus the seal, the sea, and the earth's changes became the sole subjects of his conversation as the train bore us away, and for the rest of our journey