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the ants of his own native country; we must pass over altogether his chapters on their anatomy and physiology, on the geographical distribution of the ants of Switzerland, and many curious habits of particular species. There is one point, however, which has a general interest, namely the stinging and biting properties of ants. We will give M. Forel's remarks on the subject :

• All the world,' he says, ' fears the sting of ants, and yet of the sixtysix kinds occurring in Switzerland there are not more than four or five which are really capable of piercing our skin with their sting, and of causing us a little local inflammation, which betrays itself by an itching or by a pain more or less acute, as well as by a slight redness, with or without swelling. These kinds are as follows :-(1) Myrmica rubida; the sting of this ant is truly very painful; the pain which it produces is, in my opinion, at least very great, and much more cute than that of the sting of the common wasp (Vespa vulgaris, or V. germanica). But M. rubida is not very common, and its nests are in open places, where they are seen at once, so that one is not often molested. (2) M. lævinoilis and ruginodis. These kinds, known by the name of the red ant (Fourmi rouge, rousset, rousselet, &c.), are the only one from which the public often suffer. When one has taken one's seat in woods, upon moss, or upon the trunk of a tree, by the side of brooks and rivers, it is rare that one does not come in contact with them; they quickly invade the clothes, and one feels presently in various parts, as it were, so many pricks of sharp pins. The pain is much less severe than that produced by M. rubida, and it generally disappears at the end of a few minutes. (3) The species M. scabrinodis and lobicornis seldom sting, for their disposition is not so aggressive as that of the preceding ones, and their sting is weaker. (4) The Tetramorium cæspitum bites with fury, but its bite is too short to pierce the skin, unless it be very thin (as that of infants and of the face). In this latter case it gives rise to a slight pain, or else, and this is generally so, to a simple itching. The other Myrmicide and the Ponerida of Switzerland are incapable of stinging us, their sting being too weak or too short. Amongst the ants of the genus Leptothorax want of courage is the principal cause.'

We conclude by expressing a wish that the perusal of this article may induce some of its readers to take up the study of the history of ants, with a view to verify or to correct the . wonderful things attributed to them.

Art. IV.-l. Les Villes mortes du Golfe de Lyon. Par C.

LENTHÉRIC, Ingénieur des Ponts et Chaussées. Paris :

1876. 2. On the Lagoons and Marshes of certain parts of the Shores

of the Mediterranean. By D. T. ANSTED, F.R.S. Excerpt

of Proceedings of the Institution of Civil Engineers. 1869. 3. Address to the Royal Geographical Society of London. By

Major-General Sir H. C. RAWLIXSON, K.C.B., President. .

London : 1876. 4. An Inquiry into the Soundness of M. de Lesseps' Reasonings

and Arguments on the Practicability of the Suez Canal. By

Capt. T. SPRATT, R.N., F.R.S. London : 1858. THE He effects of small, but long continued changes are more

easy to calculate than to imagine. It is hard to realise, from what takes place during an observation extending over days, or even years, the results of the lapse of centuries, or tens of centuries. It is indeed possible, from the narrowest base of exact observation, to calculate the proportions of secular distance, as the astronomer, from the restricted limits of the rotation or of the orbit of the earth, deduces the order of the planetary range. But as the eye is unable to take cognisance of those minute angular differences which are grasped by microscopic examination of the vernier, so is the fancy unable to picture, from the movement of the waterfall of to-day or of the Hood of a year or two ago, the condition to which a constant fall of water or a long series of floods will reduce the valley familiar to our infancy after the lapse of thousands of years. Nothing is more trite than the constant reference to the effects of the unwearied tooth of Time. Nothing is more familiar to the mechanic than the introduction of Time as an element of computation, and yet nothing affects us with more surprise than the result of this imperceptible, unslumbering action, when we are suddenly brought face to face with it after the lapse of a sufficient period to allow of a visible change.

In the case of those physical changes which are constantly taking place on the face of the planet earth by the agency of rainfall and water-flow, we have the most striking instance of our inability, not so much to estimate as to realise in fancy, the effects that are certain to follow in a definite period of

When deep and rapid rivers are observed to erode one bank of their channel, and to throw sand and shingle on the other, the sidelong movement of the stream, though it




may amount to miles of distance in a comparatively short time, can only be ascertained by definite measurements, taken at fixed dates. The case in which the physical changes pro

. duced by the steady operation of natural causes are most obvious, is probably that of the inroads made on a cliff of soft or friable material by the tide. We observe that a fall of perceptible magnitude has been caused by a tempest. We may note that the outlook point of the fisher, or the hut of the shepherd, is now so near the verge of the cliff, that a few more such nights as the last would be enough to place the frail tenement in peril. A little later we may see even nearer cause for alarm. Yet again comes a tempest, and our landmark has disappeared. But with its disappearance has been lost our natural and apparent means of determining where sea and shore were accustomed to border. Again, we are driven back to the aid of the surveyor or of the mapmaker to measure the rate at which the ocean is advancing, and to estimate the time within which what is now green knoll will have become sandy sea bottom.

Physical science is only in its cradle; and yet the geological theory was comparatively old before it was allowed to totter forth from the imaginary regions of vast and terrible convulsions, regarded as the great agents of terrestrial change, and to enter on the more sober inquiry into the probable effects that would be produced, or that have been produced, by the operation of existing and appreciable causes, prolonged for a long period of time. It is to Sir C. Lyell that we are indebted for first directing due attention to this important aspect of the geologic record. It is true that no one who has been a witness to the formidable activity of earthquake and of volcano even in the comparatively tranquil regions of Southern Europe, can doubt the fact that convulsions of terrific energy have left their marks on the surface of the earth. The earthquake of January 1858, though it was said to have destroyed thirty thousand persons in Calabria, only threw down a few stones from the solidly-built palaces of Naples. And yet a shock which, though alarmingly sensible to the population, wrought no further mischief in the capital of the two Sicilies, raised the whole shore of the Bay of Naples, from Sorrento to Misenum, by a permanent elevation of from six to eight inches above the former level of the sea. This movement, however, is but trifling in comparison to the successive elevations and depressions, of as much as ten or twelve feet in level, which are shown, by the attacks made by boring marine molluses on the columns of variegated marble which yet stand erect on their bases amid the ruin, to have occurred, on the same coast, since the erection of the Temple of Serapis at Pozzuoli

. Little more than a century before the occurrence of the quiet, but very appreciable, volcanic displacement of 1858, a portion of the bank of the Tagus, comprising a quay thronged with the inhabitants of Lisbon, went down like a stone to an as yet unsounded depth-so at least they assert on the spot--being severed from the undisturbed portion of the city as if it had been cut in twain by a knife.

It may seem almost paradoxical to assert that the present century is witness of a process which, if continued for a sufficient length of time, will convert the basin of the Mediterranean into a vast river valley, in which marsh and lagoon will gradually be warped up into cultivated soil, and through which the waters of the Nile and the Atbara, receiving as affluents the Danube, the Po, the Rhone, the Tiber, and other tributaries, will be poured into the Atlantic. Yet nothing is more certain than that the causes now in daily operation are adequate to effect this great physical change, provided that no geological convulsion intervenes during the period required for its completion. Not only so, but the data which have been collected and are in course of collection by hydrographers, geographers, and engineers are becoming so numerous and exact, that it may be possible, before long, to assign the period within which this obliteration of the inland sea would be effected. As the first assumption, however—that of the uninterrupted continuance of the actual geological order-is one of such unwarranted magnitude, it would be little more than scientific trifling to complete the calculation. It is much more to the point to inguire how far we can ascertain, either from historic records or by the methods of the surveyor, the annual amount of delta formation that is actually taking place in the Mediterranean. In some instances we have recently been provided with careful measurements of flow and of deposit. In other cases we have indications, more or less reliable, of the condition of the littoral in the neighbourhood of the great river mouths at given dates. Herodotus supplies us with important landmarks showing the growth of the delta of the Nile, which have never yet been either understood or thoroughly investigated. M. Lenthéric has given us much valuable information as to the growth of the delta of the Rhone. Admiral Spratt has prepared charts exhibiting the advance of the shallow banks in the delta of the Kilia, the northernınost branch of the Danube, between 1830 and 1856. From Venice comes information that the silting up of the lagoons, which Sir John Rennie, in 1819, predicted would ensue if certain precautionary measures were neglected, has made rapid progress since the Austrian engineers departed from the wiser plans of their Italian predecessors. It remains to be seen whether the information as yet accessible is sufficient to allow us to arrive at any approach to the definition of a law that would be applicable, under various cases, to the determination of the secular growth of the deltas of the rivers flowing into the tideless waters of the inland seas of Europe.

The conversion of the bed of the Mediterranean into a cultivable river valley, vast as the change may appear to the imagination, is, after all, but a special example of that steady, silent, unintermitting, and therefore mighty change that is in progress over the greater portion of the surface of our globe. The physical powers of nature, the rifting energy of frost, the parching and crumbling effect of heat, the mechanical friction of rain, the chemical action of the atmosphere, are all engaged in a mighty and combined effort to reduce the surface of the planet to its true mathematical form of a spheroid of rotation. So certain, however slow, is the result of the incessant action, that it is only to the counterbalancing effects of geological convulsions-or at least of upheavals which deserve that title by their magnitude, whatever be the rapidity with which they may have been effected—that we can attribute the fact that our globe is not now in the condition of a solid nucleus, surrounded everywhere with a watery envelope. Almost all that we can observe of the steady operation of natural causes is tending to reduce the earth to that condition. Inorganic nature hastens, we will not say to destruction, but to that obliteration of the features of individuality, which would result in the destruction of terrestrial life. The toil of man, feeble and puny as are its results when compared with those of the great agencies of nature, tends in some cases rapidly to hasten, in others slightly to delay, the assimilating process. The great conservative element which resists the erosive force of atmospheric and of aqueous degradation, is the vigorous energy of vegetation. By absorbing and distributing the mountain rainfall; by clothing and protecting the banks of rivers; by arresting the deportation of the sandy banks of the sea by the waves; and by forming a barrier to the destructive march of the sand dunes in the track of prevailing winds; forest trees, marsh and aquatic plants, creeping knot grasses, and sociallygrowing pines effect more for the maintenance of the actual condition of the dry land than any other, or than all other agencies. By mining, quarrying, draining, and similar works,

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