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The Horticultural Society has a garden in the vicinity of London, established solely for the purpose of experiment: and from this much useful information has been already procured. In France, agriculture is considered to have derived considerable advantages from the establishment of the Jardin des Plantes; and more than equal advantages may be expected to arise in this country, where the cultivators are in general much more. enlightened, and always prepared to introduce improvements of every kind. * We have chosen the Transactions of the Horticultural Society for notice, that we may lay before our readers some of the modern improvements in Gardening: in doing which, we shall pursue no particular plan; but select from the different volumes before us, those parts which we think will be most amusing.

I. We have already had occasion to notice the two papers of Mr T. A. Knight, (the President of the Society), on the motion of sap in trees; and the result of this • that the sap

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is absorbed from the soil by the bark of the roots, and carried ' upwards by the alburnum of the root, trunk, and branches; that it passes through the central vessels into the succulent • matter of the annual shoot, the leaf-stalk, and leaf; and that it is returned to the bark through certain vessels of the leaf'stalk, and, descending through the bark, contributes to the process of forming the wood.

The work before us contains several curious papers by the same author, on the subject of Vegetable Physiology, and some ingenious applications of the result of his experiments to the practical purposes of horticulture. All plants have a tendency. to adapt their habits to the climate in which art or accident places them. Thus the Pear, which is probably a native of the

* We are sorry to be compelled to remark, that the Royal Gardens at Kew partake of none of the liberality of the Experimental Garden of the Horticultural Society.-Not a single plant raised there is distributed-all access is denied, except the liberty to run through the gardens at the pas de charge, with a labourer at your heels. The great misfortune however is, that these gardens being considered as the public botanical gardens of the kingdom, all seeds of rare plants, &c. are sent there, and are therefore lost to the public.-But, fortunately, the Horticultural Society is not within the withering and baneful influence of Government Patronage; and it will, we hope, therefore flourish. If a ministerial member could ask of Lord Sidmouth the appointment of the gardener, the secretary, or the very porter or housekeeper to the Society, we should expect little good to arise from its institution, except to those who enjoyed the salary. + Vol. V, p. 92.

to drop off the stocks on the death of the parent tree. All reasoning from analogy, however, confirms us in the opinion, that it is impossible to continue, by grafts or buds, any variety ad infinitum. Mr Knight is a strenuous advocate for this hypothesis: though we think there are some points of considerable difficulty to be got over. There are many well known varieties of trees which have been cultivated in this country for a very considerable time, such as the rose, the elm, &c. without any apparent loss of vigour. These, we however are aware, are propagated by an extension of the root; and this fact Mr Knight seems to consider as likely to insure grafts a longer continuance of vigorous existence. Mr Williamson, in a paper now before us, has in some degree controverted this position, that the cause of the diseased appearance of young grafted trees arises solely from the grafts being taken from old and decayed stocks. He states that, in the course of a few years, several young trees, which had been raised from seed, began to exhibit the same diseases, and to be affected by them in a greater degree than many of our older varieties; and that it is therefore evident that old age was not the only cause of these appearances. Mr W. ascribes the premature decay to the supposed diminution of the warmth of our summers. As a confirmation of this, it is to be remarked, that the golden pippin, which with us has become a shy bearer, in France, where the climate is warm, is still considered as a very productive tree. Without entering farther into the discussion of the question, there can be no doubt of the fact, that several of the older varieties of our fruits have been gradually decaying; and we owe principally to the scientific exertions of Mr Knight, the introduction of many new and excellent varieties, which supply the loss of the old; and, from the spirit which has arisen, every season will no doubt continue to increase our stock. Knight's theory, he conceives, is confirmed by Columella, who seems to have known that a cutting of a bearing branch did not form a young tree; for, speaking of the cutting of the vineSemina (he says) optima habentur à lumbis, secunda ab humeris, tertia summá in vite lecta, quæ celerrime comprehendunt, et sunt feraciora-sed et quam celerrime Senescunt.

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The inuring plants of warmer climates to bear, without covering, the frosts, the ungenial springs, and cold summers of this country, is a subject of considerable importance to the horticulturist. Little hitherto has been done in this respect with trees, because in general the propagation has been effected by cuttings or layers from the parent plant, which have therefore, in a great measure, retained its original habits; and we are now probably growing in our gardens the identical Laurel introduced

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by Master Cole, a merchant at Hampstead,' some years before the year 1629, in which old Parkinson published his Paradisus terrestris.

Most of our present wall trees are merely continuations, by grafts, of trees raised in a warmer climate; and although it is not probable that either near London or Edinburgh the peach tree will ever be brought to bear fruit so perfect and so delicious as that which is ripened in warmer climates, much may be expected from the production of new varieties, raised in the manner suggested by Mr Knight's experiments, to procure early fruiting apples, and which shall have the kabit of enduring our rougher climate. It is probable, observes Sir Joseph Banks, that wheat, now our principal food, did not bring its seed to perfection in this country till hardened to it by repeated sowings; and though some spring wheat from Guzerat, which was sown by him, eared and blossomed with a healthy appearance, many ears were, when ripe, without corn, and few brought more than three or four grains to perfection. Some seeds of Zizania aquatica were sown in a pond: the first crop produced strong plants and ripe seeds, the produce of which, however, was in the next year weak, and not half the size of the parent plants; but in each succeeding year they grew stronger, and in a few years attained their full size. Thus a plant, at first scarcely able to bear the cold summer of England, in fourteen generations became as strong and as vigorous as our indigenous plants.

III. The creation of hybrid or mule productions, from two plants of distinct species or varieties, by fecundating the blossom of one with the farina of the other, is also one of the ingenious devices adopted by Mr Knight, in order to obtain varieties of fruit, partaking of the different qualities of the two parent plants. Mr Herbert (Vol. IV. Part 1.), as far as we can understand him, is persuaded that, by such intermixtures, new species may be created amongst vegetables, capable of continuing a distinct race by the natural descent of an unadulterated progeny to an indefinite extent, and without reverting to the single form of either parent plant. It is impossible to conceive any thing more improbable than such a position; and we entirely concur with the opinion intimated on this point in the Botanical Register (Vol. III. p. 195.), that no truly hybrid 'plant, under any circumstances, will continue an unadulterated descent through seeds, beyond a very limited number of degrees; and that the less complete productions of this kind, such as take place between remarkable varieties of one species, revert to the single likeness of either one or the other parent, or assume new appear ances in endless vicissitudes.

Yorkshire to Dunnose in the Isle of Wight, a remarkable anomaly appeared, for which it was very difficult to account ;-the degrees, instead of increasing with the latitude, seemed, if the measurement could be trusted, to decrease. Thus, for latitude 51° 2' 54", a degree in fathoms, as given by Colonel Mudge (Phil. Trans. 1803), was 60884; for lat. 52° 2′ 20′′ it was 60820; and for lat. 52° 50' 30" it was 60766. Hence we should be led to suppose that the Earth, instead of being flattened at the Poles, is more elevated there than at the Equator, contrary to the received notions of its figure. The apparent variance between these results and the results obtained by the National Institute, led Don J. Rodriguez to examine the matter, in order to reconcile the difference and to detect the error which he concluded must exist in the English observations; and, without adverting more particularly to his measurements and calculations, we may state that he ascribes the appearance of progressive augmentation in the degrees, to error in Colonel Mudge's observed latitudes. (Phil. Trans. for 1812, p. 336.) Bearing this in mind, Captain Kater prepared to ascertain the latitudes at the stations in question with all the exactness possible. The corrections for precession, &c. were those used at Greenwich Observatory; and the mean polar distance of the Pole Star, was taken from the latest observations of the Astronomer Royal. The mean of five series of observations, made between the 3d and 12th of October, gave the latitude of Clifton Beacon 53° 27' 29".89. The observed arc between Greenwich and Clifton Beacon, as given by Colonel Mudge, was 1° 58' 51".59. Add this to the latitude of Greenwich, 51° 28′ 38′′.01, and we have for the latitude of Clifton Beacon, 53° 27' 29".6, differing only by 0".29 in defect from that obtained by the repeating circle. gain, at Arbury Hill, the mean of three series of observations, made on the 18th, 22d, and 26th of October, gave the latitude equal to 52° 13' 25".72. The observed arc between Greenwich and Arbury Hill was 0° 44' 48".19, which therefore gives 52 13' 26".20 for the latitude by the Trigonometrical Survey; differing only 0.48 in excess from the latitude obtained by the repeating circle. Lastly, the latitude of Dunnose was found by the repeating circle to be 50° 37' 5".27, and by the zenith sector, 50° 37′ 6′′.61; the difference being 1".34 in excess. It is very probable that this difference, small as it is, arose Captain Kater being compelled, by the nature of the groups take a station at some distance from that used in the He chose Shanklin Farm instead of Dunnose; and was so unfavourable for measuring a base, that th difficulty in connecting the two points. We

titled to ascribe the discrepancy in this case to the circumstance now mentioned, because the difference was so very minute in the other stations where the points of observation coincided. That these latitudes, then, are as correct as observed latitudes can be, we may safely assume; but it is possible that they may differ from the true latitudes of the several stations. If this difference can be accounted for, the anomaly above alluded to will be satisfactorily explained.

The diminution of the force of gravitation from the Poles to the Equator, may be found by the difference of the lengths of pendulums oscillating in equal times at the Poles and at the Equator; or by the ratio of the squares of the number of vibra tions in 24 hours, observed in different latitudes, with the same pendulum. The diminution indicated by the decrease observed to take place in the number of vibrations between any two given latitudes, must be the same, from whatever portions of the me ridian it is computed, unless it be affected by some irregular attraction. But it is found from observations at Unst, and each of the other stations in succession, that the diminution deduced from the arc between Unst and Portsoy, is less than that obtained from the arc between Unst and Leith; the number expressing the diminution being .0053639 in the former case, and .005480 in the latter. When Unst and Clifton are the two latitudes, the diminution is .0056340; Unst and Arbury Hill give .0054282, denoting an increase of gravitation; Unst and London give .0055510; and a still further decrease appears from comparing the observations at Unst and Dunnose, the diminution thus obtained being .0055262. Again, Purtsey and Dunnose give .0055920, being a greater dimination than the last mentioned. Clifton and Dunnose make it only 0059515 which is smaller; while Arbury Hill and Dunnose give 1060212 which is greater than any of the preceding

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