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such works as “Lear” or “Othello." And yet, in one way at least, we share Mr. Carlyle's regret. What student of Shakespeare could doubt that that omnipotent genius might, had he so willed it, have accomplished for prose fiction what he has accomplished for the drama—have been the first of prose novelists, as he is the first of poets? Had he taken up the novel where Greene and Lyly left it, it is not likely that England would have had to wait a century and a half for a genius like Fielding, and more than two centuries for a genius like Walter Scott.

But we must bring this sketch to a conclusion. A careful examination of Shakespeare's prose is still a desideratum, and it would, we are convinced, be a welcome accession to our present stock of Shakespearian criticisms. Unless we are much mistaken, such an examination would be, moreover, of inestimable value in affording internal evidence bearing on the chronology of the poet's works. His verse has been scrutinised with ludicrous minuteness : his prose remains virtually without a critic. Our literature has not yet found its Tiraboschi. Indeed, the history of our prose literature has never even been adequately sketched; but of one thing we feel very certain : that whenever such a work appears, the name of the greatest poet the world has ever beheld will be found to hold a high place, not only among the fathers, but among the masters of English prose. To judge him properly, we must judge him relatively.

J. CHURTON COLLINS

SCIENCE NOTES.

LAVA FLOODS WITHOUT VOLCANOES.

O

RTHODOXY and heterodoxy, conservatism and radicalism,

and all other isms and schisms that fetter free judgment, are supposed to be non-existent in the scientific world. Sometimes it comes out, however, that with all our struggles to maintain an intellectual independence, we have been blindly following a theory that could not have been accepted had we not been far too submissive to established authority.

A case of this kind has just started forth. For my own part, I am somewhat ashamed of the fact that I have twice walked round the Antrim coast, and admired the vast sheets of basalt that are spread in such mighty floods throughout that region, and are seen in such massive sections on the coast, as at Fair Head, the rocks above the Giant's Causeway, &c., that I have accepted the general belief that the columns of Staffa are connected by submarine continuations which extend farther on towards Iceland ; that I have even written a paper questioning the theory that describes that curious conglomerate, seen under Dunluce Castle and other places, as ancient “crater necks,” and, besides this, have climbed Vesuvius, and walked from Messina to Catania over the porous black lava streams of Etna, and yet have been content blindly to accept the teaching which attributes the Antrim lava to volcanic eruptions of similar kind to these, and this in spite of the absence, throughout the Antrim basalt region, of any cones or craters, or any vestiges of craters, beyond these supposed “crater necks,” for which I claim a totally different origin.

It is some consolation, however, to find oneself sinning in good company; a superficial geologist like myself is, after all, no worse than the best geologists of this generation. This sort of penitence and consolation will possibly be shared by some of my readers when they learn what Mr. Archibald Geikie has recently been doing and writing. If he is right, the orthodox volcanoes, consisting of craters and cones, had no existence during what I may call the basaltic epochs, nor are any such “burning mountains" at all demanded to

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account for these vast lava-streams, nor for others of still greater magnitude that he has recently visited in that wondrous country about the Yellowstone and Snake Rivers; and he further shows that the real sources of these lava floods are so simple and obvious that the Geological Society ought to sit in sackcloth and ashes at not less than half a dozen of their forthcoming meetings.

He describes portions of his journey of several hundred miles through the volcanic region of the Yellowstone and Madison, riding for days over fields of basalt as level as lake bottoms among the valleys, and then emerging from the mountains“ upon the great sea of black lava which seemed to stretch illimitably westwards," and appeared as if the great plain had been filled with molten rock, which had kept its level and wound in and out, along the bays and promontories of the mountain slopes, as a sheet of water would have done. The precipitous walls of the cañon cuttings of the Snake River show that the plain is covered by a succession of parallel sheets of basalt to a depth of several hundred feet. He looked in vain for any central cone from which this great sheet of basalt could have flowed. “It assuredly could not have come from the adjacent mountains, which consisted of other and very different lavas, round the worn flanks of which the basalt had eddied.”

How, then, could these vast floods of lava have originated? Mr. Geikie answers this question by resuscitating the explanation of Richthofen, which has been practically snuffed out by modern geologists. This theory regards all such great accumulations of basalt as due to the welling forth of molten rocks from great fissures of the earth-crust, out of which the melted rock has flowed quietly and steadily, without any of the roaring and raving and violent ejections due to the escape of high-pressure steam or other imprisoned gases. The cones which surround the craters of Etna, Vesuvius, Stromboli, &c., have been formed by the action of such outbursting gases, which fling masses of lava high in the air, to fall down and be upthrown again and again, until pulverised by the mutual collisions of the upflying and down-falling fragments. This powder and these

-. fragments, as they fall on either side of the volcanic throat, pile themselves as a cone, over which the lava flows and builds it higher ; and thus on till a mountain is formed.

An outflow of mere liquid from a long chasm or fissure would make no such heap, but simply form a spreading stream that would flow like water down a slope, or spread out on a plain, or fill up a basin-shaped valley. But where are the fissures or chasms? may next be asked. They

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abound in our own country and in the regions above referred to; but they no longer remain as chasms or fissures, for the simple reason that the molten stream has cooled and solidified within them, and thus has filled them with material corresponding to the lava streams around.

These filled-up fissures are the "trap dykes," so very abundant and so familiar to geologists, and even to the geological tyro. In the British Islands alone these filled-up fissures are found extending over an area of above 100,000 square miles, and may be counted by hun. dreds or even by thousands. They are not only sufficient to account for all the remaining basaltic or trap formations, but indicate the existence of other similar outflows that have been subsequently denuded.

According to this view, the upthrowings of volcanoes are but minor efforts — mere secondary or residual phenomena—and the cones and craters, up whose black cindery slopes we climb so laboriously, are comparable to the pimples that sometimes form on the edges of a healing wound.

I cannot conclude this note without adding an argument of my own in favour of Mr. Geikie's view. All the recent lavas that I have seen on the flanks of Etna and Vesuvius, though chemically resembling basalt, have a totally different mechanical structure. They are porous, actually spongy ; and this porosity is evidently due to the intermixture of gases with the semi-fused solid, just as the carbonic acid of fermentation is mixed with the dough from which bread is made. These pores afford evidence of the existence of the imprisoned gases to which violent eruptive volcanic action is due ; and their absence in basalt and other varieties of trap rock is an evidence of the absence of such gases, without which neither cones nor craters corresponding to those of orthodox volcanoes could be formed.

If these great lava streams had been poured out under the sea from submarine volcanoes, as Lyell and others suppose, the sudden cooling of their surface would increase the porosity of the interior by preventing the gradual emission of the gases during solidification, just as the baker obtains very porous French rolls by rapidly solidifying his "sponge."

Neither will the idea that the solidity of basalt, &c., is due to subsequent introductions of other ingredients, or what Lyell calls "secretion during the cooling and consolidation of lavas," bear examination. It is refuted by the experiments made about twenty-two years ago by Messrs. Chance, which I witnessed. The “Rowley

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Rag," a basaltic rock, was fused and run into moulds for architectural decoration. When suddenly cooled it formed a black glass, not distinguishable from obsidian ; when slowly cooled, by keeping the moulds red-hot for several days, it consolidated into a granular mass, scarcely distinguishable from the original rock.

ELECTRIC HAIR.

A

T the Academy of Sciences, in Paris, a paper was recently read

by M. Amat, in which he recounts some experiments he made in the North of the Sahara. By passing a pocket comb through his hair or beard he produced sparks of 5 to 7 centimètres in length in hot, dry weather. Horses' tails presented still more striking electrical phenomena, which he attributes to the ill-conducting horny matter of the hoof effecting better insulation from the earth than is obtained by the human foot. He states that the sparks above described were obtained from himself without insulation, and that insulation increases the intensity of such phenomena.

I have made similar experiments myself, using different kinds of combs, and find that real tortoiseshell is much more effective than ordinary horn combs, and horn better than bone; also, that vulcanite is about equal to tortoiseshell, and that-other conditions being equal—the experiments are more successful during frosty weather, with easterly winds, than at other times. This is, doubtless, owing to greater dryness of the air. My experiments do not confirm what M. Amat states respecting insulation, i.e. insulation by the feet. I tried this many years ago, and, finding no perceptible difference, concluded that the necessary insulation is effected by each individual hair on its own account. This was confirmed by the fact that dryness and length of hair appeared to be--next to atmospheric dryness--the chief condition of success. If I am right, the length of the hair on the horse's tail has far more to do with its electrical excitability than the supposed insulating power of its hoofs. Cats are celebrated for their electrical properties, and they have no hoofs. Their fur itself is highly electrical, as we know by experiments made upon their separated skins. A cat's skin, or a fox's tail, is an admirable rubber for an electrophorus.

Some years ago I witnessed, in Edinburgh, some very striking experiments made by an eminent tragédienne on her own hair. By rapidly rubbing it in a dark room (with a tortoiseshell comb, if I remember rightly) she brought out brilliant flashes, produced by a multitude of sparks, accompanied with loud crackling. Her hair

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