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agriculture spread his table, the hamster is even more carnivorous than herbivorous; that is to say, he prefers animal food whenever he can have it. His own species, rats, mice, small birds, lizards, May-bugs and other chafers, caterpillars &c., are greedily devoured by him. In eating vertebrated animals he always begins with the head. When a sparrow or other small bird, whether alive or dead, is presented to the hamster, the first and evidently instinctive action of the latter is to break the wings. I have kept several dozens of this animal in large rooms, providing them with a great variety of green fodder, seeds, and artificial dishes, yet every night the weakest of the company were devoured, and others so severely wounded that they had no chance of escape the next night. By this fondness for animal food the hamster in some degree makes amends for his depredations, for there is no useful animal to which he is dangerous, not even to the partridge, as the same fields near Gotha in which the hamsters swarm, are well stocked with that bird. Besides, in captivity he eats, with great delight, all sorts of pastry, bread, butter, cheese, broth, &c., and is apt to become a great gourmand. On the other hand, he is not at all addicted to drinking, nor particular in the choice of it. He can live four weeks without water, and his health will not suffer; and in the fields, as his rambles do not extend far, he must often content himself for long periods with dew and the juices of succulent herbs. In this he is, no doubt, greatly assisted by being underground about twenty hours out of the twenty-four, which must prevent perspiration in a great degree.

Disposition. The celebrated Professor Blumenbach used to say in his lectures, when treating on the Mus decumanus, “ Thank heaven, gentlemen, that species is not as big as an elephant; if it were so, the human race would have ceased to exist long ago.” The same might not be said, it is true, with an equal degree of probability about the hamster, as he is greatly deficient in that cunning and agility which would render the ferocity of the Mus decumanus so dangerous and destructive, if great physical power were superadded to its other qualities ; yet in point of brutal ferocity the hamster surpasses even that rat.

The latter is more sociable, more gregarious in its habits; it will not kill and devour its congeners, though of an exceedingly sanguinary disposition, except when hard pressed by hunger; whilst the hamster never falls in with another individual of its own species, without trying to make it its prey, the weaker, if not killed, generally making its escape more or less severely wounded. Even the

two sexes live together and in peace only during the few days of each breeding season.' With this single exception the hamster may be said to be constantly at war with every living creature or moving object which happens to come near him. It will jump with equal fury at a waggon-wheel or at a horse travelling along a road which a hamster is about to cross in the same place, and a young hamster will sometimes do so as well as an old one. Horses have now and then been frightened by the screams and bites of this little animal in the dusk of the evening, so as to run away. From men or dogs the animal will commonly, though not always, try to escape; it then takes the nearest course to its burrow, from which it is seldom at a great distance. When its pouches are full, it always takes to its heels at first, and if its burrow be only at the distance of twenty or thirty yards, it tries to regain it with its cargo, but never fails to pop its head out of the hole, screaming furiously in defiance. If the burrow be farther off, it tries to get a little a-head of its pursuer, in order to have time to empty its pouches; whereupon it rises upon its hind legs and faces its enemy, blowing (whereby the pouches become distended), squeaking, screaming, and jumping against the intruder to the height of from one to two feet. When the enemy retreats a little, the hamster hops after him like a frog. At such times the animal is quite beside itself with fury, caring for no wounds, and fighting till death.2 Old hamsters do not usually retreat before man, when sitting before their burrows with their pouches empty; I have myself killed several under such circumstances.

Some breeds of dogs, as pointers and large terriers, soon acquire a knack of killing hamsters at one bite, by catching them by the middle of the chest; but when the animals are better matched, the combat is protracted, and the hamster often succeeds in gaining its burrow, after repeatedly beating back the dog. This obstinacy in fighting, in spite of all wounds not absolutely mortal, makes the hamster gain the victory over the rat. A combat between old individuals of the two species, lasts very long, but ends with the death of the rat. In short, as far as my own experience goes, I must believe the hamster to be the most courageous animal. Unfortunately there is no other commendable feature in his dis

1 For further proofs of the ferocious and reckless disposition of the hamster, see also below, under the head of Propagation.

2 The bites of the hamster penetrate to the depth of half an inch, but are not particularly dangerous, even when the animal is furious.

position; he is perfectly untameable, and cannot be broken by any sort of education.

(To be continued.)

Art. II.-Illustrations of the Geology of the South East

of Dorsetshire. By The Rev. W. B. CLARRE, A.M., F.G.S.

(Continued from page 238.) From this examination of the composition of the coast line, we have now to advert to the phenomena presented by it, in connection with the underlying chalk. And I have, first, to remark, that if my attempt to explain the singular conformation of the cu red and vertica chalk beds at Ballard Head (see Mag. Nat. Hist. Sept. 1837) needed any further elucidation, we have the fullest evidence of the vertical up-cast of the whole of the chalk between the Ballard Head fault and Old Harry Point, not only in the derangements on the Studland side, and in the perpendicular rents or fissures through the nearly horizontal chalk beds, but in the inclination of the plastic clay beds at the Red Rock cliff. For there is no means of explaining that inclination, but the supposition of the chalk having been bodily up-heaved, and lifting with it the plastic clay beds, which became, in consequence, tilted up at the point of contact and for some little distance, and broken into portions by the giving way of the soft strata at those parts now occupied by the ravines which lead from the sea to the village of Studland. It is also clear, that if such were the case at a distance from the chalk, the beds would, beyond the last point of fracture, retain their original horizontality, which is the case farther off from Studland. This will appear very plainly, if we see by the map that the plastic clay abuts upon the chalk on the north side of Ballard Down, far away from the vertical chalk, and, therefore, nothing but an elevation of the chalk en masse, or a depression beyond Studland, subjecting the northern end of the inclined beds to a down-cast motion (for which there is no evidence in the vicinity), can have produced the phenomena presented by the Red Rock and adjacent cliffs.

In order to explain this more fully, it must be mentioned that the Studland rock is, in some degree, a separate portion of the plastic clay. Seen from a distant elevation, such as the hills on the north side of Poole Harbour, Studland appears to be a small table-land lying on the edges of the east and north slopes of the chalk, and separated from the moun

1 Mr. Lens quotes an instance of an albino which became very tame.

tainous declivities of Studland Heath by a valley. Now such is actually the case, for between the chalk and Studland there is a deep diluvial excavation, which, in short, is continued all along under the chalk, thereby insulating all Studland Heath and Studland itself by dry straits, one of which now affords a bed for a winter stream that finds its way through one of the cracks in the cliffs into the sea. This fact would, I know, be used differently by some geologists, who contend that running water scoops out its own channels, even in the hardest rocks, and, therefore, say they, sand but lightly agglomerated must give way. Thus, the chines along the shore of Poole Bay, are by Mr. Lyell said to be the result of the streams that flow through them to the sea. If so, of course, the Studland 'cracks’ or chines have no right to be deemed worth notice. But how stands the case? A violent and powerful torrent, bearing with it gravel and fragments of angular rock, tosses these extraneous matters about in the hollows of its bed, and they, acting like a mechanical machine, bear away the moistened bed, till they cause that bed to descend deeper and deeper in the solid rock below ;-and, therefore, it is said, a sluggish stream must, of necessity, bore away in sand with less trouble and more effect !

Now, I am not unaware that there may be cases found, where the torrent has assisted in eating out a deeper channel to a certain limited extent,—but I am not satisfied with the assertion that this extent may be unlimited. The river Sioule in France is quoted as an example. That river now runs at a level through nearly vertical walls of basalt and gneiss, much below what it formerly did; and this is shown by a ledge of gravel much above its present bed. This gravel-deposit marks a period, it is assumed, when the river had only eaten down so deep in the solid rock. It is said, that the Sioule has cut through more than 100 feet of compact basalt, and at least 50 feet of gneiss.

But if the theory of these stone-eating waters be true, there ought never to have been any gravel above, left on any ledge, or else there ought to be a slope of gravel all the way down. The river has descended certainly, but it must have suspend


1 See Messrs. Lyell and Murchison ‘On the excavation of valleys, as illustrated by the volcanic rocks of Central France;' G. P. i. 39, and Edin. Phil. Journal: also Prof. Sedgwick's Address to the Geol, Society, Feb. 19, 1830, for facts and comments. After giving a luminous account of the different modes of excavation, the latter distinguished author and observer sums up with an allusion to the Auvergne rivers. These are great authorities, and it may be presumptuous to dispute their judgment, -but geological doubts often lead to geological truth.

ed its consumption of rock in order to have left its old bed to accumulate,--and then eaten away most furiously to have got so low without any trouble or traces of its progress. Suppose, however, we assume the case of the Sioule to be the counterpart of the examples presented by raised beaches, or what, perhaps, is nearer the fact, that after its old channel was blocked up by a lava-flood, as was the case, a convenient operation of volcanic forces suddenly burst open this barrier, and split the rock vertically downward, and the whole mystery is solved. And if any person will carefully consider the thousands of examples that are scattered over the surface of England,—nay, if he will confine himself to known and familiar cases, those of the chalk range, which is everywhere fractured to give way to rivers that had no other outlet,-or those of Herefordshire, which pass through similar openings in the old red sandstone,-it will be found that rocks of every formation exhibit one and the same phenomenon respecting rivers and streams, and that these occupy beds made for them by disruptions of the strata, and not beds which they have made for themselves by their own action. And why should these sandy chines be an exception?

It is urged that the sand is full of springs, and that, near Bourne Mouth, under the signal-staff, the cliffs do visibly founder through the continual action of land-springs. No doubt such is the case; but where is the parallel between this foundering of a whole surface of cliff, and the regular gradual hollowing out of one deep and deepening channel ? Moreover, it can be shown (and will be) that these chines are nothing but diluvial furrows, which gave direction to the diluvial waters, because they were suddenly formed, and which now afford a similar passage to the springs that are seen to well out, not at the level of the top of the sides of the valleys, but at some distance vertically below that level,—the valleys being excavated above and beyond their origin. Such also is the case at Studland. The


streams that occupy an inch or two in depth of the ravines through which they flow, rise a considerable way vertically above the height of the walls of the ravines, and before they reach the ravines have not excavated the sand over which they run, but follow the natural declivity of the ground. It may, finally, be said,look at Niagara -(sic parvis componere magna)-see how it has eaten its way backward towards Lake Erie! The reason of this retrograde reform—this 'advancing of three steps backwards'-is obvious. The soft marl is destroyed, and, therefore, the limestone interstratified with it is destroyed ;but has Niagara, since the day it left its old fall at Queens

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