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other trees, which Professor Burnet thinks may be owing to the imperfectly conducting power of the dense mass which composes the head of this tree; for, though pines and firs grow higher, yet they are of lighter forms, and their inferior conductibility, from the resinous nature of their wood, may in some measure protect them. Some very remarkable instances of oaks being struck by lightning are recorded in the Philosophical Transactions by Sir John Clark, who thus writes:- "Being lately in Cumberland, I there observed two curiosities in Winfield Park, belonging to the Earl of Thanet. The first was a huge oak, at least 60 ft. high, and 4 ft. in diameter, on which the last great thunder had made a very odd impression; for a piece was cut out of the tree, about 3 in. broad and 2 in. thick, in a straight line from top to bottom; and the second was, that, in another tree of the same height, the thunder had cut out a piece of the same breadth and thickness from top to bottom, in a spiral line; making three turns about the tree, and entering into the ground about 6 ft. deep." Professor Burnet saw, in July, 1828, the ruins of a very fine oak at Pinner, Middlesex, which had the whole of its arms severed from the trunk at their junction with it, and scattered on the ground. The trunk, which was about 10 ft. in girt, was completely stripped of its bark, and shivered from the summit to the root. Perpendicular clefts passed into the heart wood, and rent through the trunk in many places, so that splinters of 6 ft., 8 ft., or 10 ft. long, and 3 in. or 4 in. thick, might be pulled out; one of which," adds the Professor, "I have." (Amæn. Quer., fol. 9.) The same year, and in the same month, we observed, close by St. Albans, an oak tree by the road side, which had been struck by lightning the night before, and from the trunk of which a narrow strip of bark had been torn from the summit to the root; the trunk being not otherwise injured, though several branches were broken off. An oak in the New Forest "had nearly one quarter of the tree forced away from the body, and several of the massive limbs of the upper part driven from their sockets a distance of several feet." (Brand's Journal.) 'It is not improbable," says Professor Burnet, "that the liability of the oak to be struck by lightning may have led to the dedication of that tree to the god of thunder."

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Fig. 1643. represents an oak, growing in the parish of Weston, in Norfolk, which was struck by lightning on the 26th of September, 1828. The drawing was taken immediately after the accident, and represents correctly the damage sustained, as it appeared at that time: but since then the standing bough has fallen, and the tree is otherwise fast going to decay. Not the slightest portion of bark was left upon the trunk, although not a single bough was stripped, nor were the leaves torn off. The fissures reached from the top to the ground, but not in connexion; gradually decreasing downwards, except the lowest, which decreased upwards. Pieces of bark were thrown to the distance of 90 yards. This was one of six trees standing in a line, and not the tallest. In the summer of 1822, a fine oak was struck by lightning, which was growing on Scottow Common, in the same county; but which, so far from being killed, continued to grow and flourish till 1828, when it was felled, and proved to be a sound and good tree in most parts. This tree was large and wide-spreading, affording shade in summer, and shelter in the winter, to the stock turned out to pasture on the common; and, before it was injured by the lightning, often attracted attention from the number of animals which were collected under it, and which it covered. From the time of its being struck, however, not a head of cattle was ever seen near it; the animals not only refusing to avail themselves of its shade, but obviously avoiding the tree, as if it were disagreeable to them. The above facts were first communicated to the Magazine of Natural History (vol. ii.), by the Rev. T. W. Salmon of Weston Rectory, and have been since sent to us, for this work, by Mr. Girling of Hovingham, Norfolk.

The roots of the oak not being so liable to rot in the ground as those of the elm, the beech, and other trees, full-grown oaks are, consequently, not so liable to be blown down by high winds as the elm. The height of the oak being less

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in proportion to its breadth than that of most other trees, may be another reason why it offers a firmer resistance to storms. Notwithstanding this, terrible devastation has sometimes been effected among oak trees by the wind; and one of the most fearful instances occurred in October, 1831, when a destructive hurricane ravaged a considerable portion of the park of Thorndon Hall, the seat of Lord Petre, near Brentwood. The following account is abridged from that sent to the Magazine of Natural History by J.G. Strutt, Esq. :-"The blast came on about eight o'clock, and in less than four minutes the work of havoc was completed. The wind came from the south-west, and entered the park near the Lion's Lodge, where it threw down a small portion of the paling. It then traversed the park in a varying sweep of about 150 yards' breadth. Near the lodge, several oaks, 60 ft. high, were torn up by the roots, with adhering masses of earth, 14 ft. in length, and from 3 ft. to 4 ft. in thickness.

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The stems of many trees were torn off within a few feet of the ground; and others merely had the head or branches broken, without being entirely detached. (See fig. 1644.) Whole trunks, huge limbs and branches, with immense masses of earth, were mingled on the ground in such a manner as to give the idea of a battery of heavy artillery having been directed against the trees in that part of the park. In some instances the stems exhibited "the appearance of having been cut off, and in others they are rent from top to bottom, or have had their giant limbs twisted off, as if they had been but so many twigs." Lofty oaks were struck near their summits, and immense portions of their upper limbs and branches were torn down, but not quite severed from the trunk, and, with their heads resting on the ground, formed "a sort of tent of foliage upwards of 30 ft. high.... Several oaks had at least a dozen immense branches torn off, while the bare and desolate-looking trunk was left standing; and, in many instances, the limbs and branches of standing trees were twisted

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and interlaced in a variety of fantastic shapes. More than 300 trees were torn up, or shattered so much as to render it necessary that their remains should be felled. This park, during the war, furnished some of the finest naval timber that could be procured in the kingdom." (Mag. Nat. Hist., vol. vi. p. 107.) We have also received from Henry Lee Warner, Esq., of Tibberton Court, Herefordshire, an account of a hurricane which occurred there in December, 1833, which destroyed a magnificent oak standing on his lawn. This noble tree had a trunk 31 ft. high to the fork, where it divided into 12 large limbs, and 14 somewhat smaller branches; altogether forming an enormous head. The circumference of the trunk was 19 ft. 8 in. at 4 ft. from the ground, and 15 ft. 4 in. at the height of 26 ft. The tree was stag-headed, and appeared to have been for some time in a state of decay. After the tree had fallen, the roots, on examination, were found in a decayed state. "The trunk, or body, which, 20 years before, was perfectly upright, had been gradually losing its perpendicularity, inclining more and more to the south-east, till it got without the line of direction; and then with its immense head it fell by its own weight. It is a curious fact, that, although the greater part of the roots had perished, and the tree was stag-headed and the boughs without leaves, yet the body was perfectly sound. The boards and quarters which the sawyers cut from it are of the firmest and most beautiful texture.-H. L. W."

Diseases. There are few or no diseases peculiar to the British oak. The honey dew, though very frequent on young oaks, is not peculiar to that tree. The punctures of certain insects, which produce galls and other excrescences, and which may be considered as diseases, will be hereafter mentioned.

Vermin and Insects of different Kinds which feed upon the Oak. The wild animals which live upon acorns, we have already observed (p. 1789.), are numerous; but those which are chiefly injurious to man are such as eat the acorns after they have been planted, or the young trees. The insects which live upon the oak are all more or less injurious to it; and these are very

numerous.

Vermin. The most general enemy to planted acorns, and also to young oak trees, is the field mouse, an account of the ravages of which in the Forest of Dean has already been given (p. 1806.). The water rat is also believed to feed on the acorn, and the squirrel is known to depend principally on it for its winter provision. Neither of these two animals, however, are generally in sufficient numbers near nursery gardens, or extensive grounds about to be planted, to be productive of any serious injury; for the squirrel is never found at a distance from full-grown trees, nor the rat from the banks of rivers or streams. The mode of entrapping mice in the Forest of Dean has already been given, and other modes of catching these, and other animals considered as vermin relatively to trees, will be found in the Encyclopædia of Arboriculture. Insects. The British oak, probably both on account of its large size, and the peculiar nature of its juices, is attacked by a far greater number of insect enemies than any of the other trees of this country. Many of these insects are, of course, confined to this tree, but many feed indiscriminately upon the beech, birch, and hazel, as well as upon the oak: thus, as it would seem, says Mr. Westwood, to whom we are indebted for this article, clearly proving, not only the very natural character of the order Amentàceæ, but also the equally natural distribution of the insects themselves into genera, consisting of species, all of which are either generally amentaceous in their food, or are confined to the oak or the birch alone. With respect to the number of species which are found upon the oak, we have the authority of Mr. Stephens (who must be considered as the most general practical collector of English insects) for stating that nearly half the phytophagous insects of England are either exclusively, or partially, inhabitants of the oak. Messrs. Kirby and Spence have given a calculation, from which they adduce the opinion, that the phytophagous and carnivorous insects are nearly equal in point of number of species; which would give about 2500 as half of the Phytophaga: but to this

number, as inhabitants of the oak, must be added the vast quantities of Ichneumonidæ, and other parasites, which feed upon the phytophagous species themselves. Perhaps the estimate here given may be found to be too great, although every one accustomed to collecting knows that the oak furnishes by far the greatest portion of his captures. Perhaps, if we give 2000 as the number of oak-feeders and their parasites, we shall scarcely run the risk of overrating the quantity. Lesser long ago said, "Le chêne suffit à en élever plusieurs centaines d'espèces différentes." (Théologie des Insectes, tom. i. p. 199.)

The solid Wood of the oak serves for the food of various insects, chiefly whilst in the larva state. Amongst these, the goat moth (Cóssus Lignipérda, p. 1386. fig. 1233.), the wood leopard moth (Zeuzèra æ'sculi, p. 887. and fig. 636.), the small stag beetle (Dórcus parallelopipedus, p. 886. fig. 635.; Gyll. Ins. Suec., i. p. 67.), and the Sinodéndron cylindricum (p. 1225. fig. 1048.), are occasional inhabitants of the oak. Several other species of lamellicorn and longicorn beetles are also inhabitants of this tree: of these, the great stag beetle (Lucànus Cérvus, fig. 1645.) is the most abundant, as well as the largest. The larva of this insect (a) feeds upon the putrid wood of the oak. (Gyllenhal Ins. Suec., i. p. 65.) It is a large, whitish, fleshy, grub, like that of the cockchafer (Melolontha vulgàris); and it is furnished with three pairs of legs, attached to the three anterior segments. In general, it lies on one side, with the body curled up, so that the tail nearly touches the head. The structure of the jaws of this larva is very similar to that of the caterpillar of the Cóssus; although, in the perfect state, it is impossible to discover two insects more completely unlike each other. When it has attained its full size, it constructs a cocoon of chips of wood, agglutinated together, within which it assumes the pupa state, in which the immense mandibles of the imago are distinctly visible (6). The female pupa is, of course, destitute of these large jaws, these organs being but of comparatively small size in that sex when arrived at the perfect state (c). The beetle seems to subsist entirely upon fluids, which it laps up by means of its long pencil-like lower jaws and lip.

Trichius variabilis is another lamellicorn beetle, the larva of which feeds upon the wood of the oak. It is occasionally found in Windsor Forest, but is of great rarity in this country. Its larva is very similar to that of the cockchafer. A beautiful figure of the perfect insect, which is also found upon, and within, the stumps of rotten oaks, is given by Curtis. (Brit. Ent., pl. 286.)

The larvae of the longicorn beetles, on account of their generally large size, are destructive to trees; but they are comparatively of rare occurrence in this country, if we except the musk beetle, found in willows. In tropical climates, where the perfect insects attain a gigantic size, they must be as injurious as the Cóssus larva. These large wood-feeding larvæ, or some of them, at least (and it is not clearly proved which), were considered by the Romans as great dainties, and are still greedily devoured by the negroes in many tropical climates. We will not quarrel with the tastes of these Acridóphagi and Campóphagi, because there can be no reason why a larva, which feeds upon wood, should not be as nutritious as an oyster or a shrimp; but we will quote a short passage relative to the subject, from the observations of the celebrated African traveller, Smeathman:-"The larvæ of all the beetles that feed on decayed wood seem to be rich and delicate eating; so that every forest in the torrid zone affords a man plenty of very wholesome and hearty nourishment, who has an instrument strong enough to cut in pieces the decayed trees. This knowledge might have saved the lives, perhaps, of many seamen who have been shipwrecked on desert equinoctial shores, which are generally covered with thick woods. The very best kind of vegetable food is but poor nourishment for the labouring Europeans, if not accompanied with animal flesh, or, at least, with animal or vegetable oils; and such food as seamen in distress meet with, as above mentioned, have oftentimes very acrimonious qualities, and are dangerous, even in small quantities, to those who eat them

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