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On the Reproduction of Buds. By Thomas Andrew Knight, Esq. F.R.S. In a Letter to the Right Hon. Sir Joseph Banks, K.B. P.R.S. Read May 23, 1805. [Phil. Trans. 1805, p. 257.]

Mr. Knight begins his paper by stating, that every tree, in the usual course of its growth, generates the buds that expand in the succeeding spring; but if these buds are destroyed, during the winter or early part of the spring, other buds are in many species generated; which buds perform the office of those that previously existed, except that they never afford blossoms or fruit. This reproduction of buds has not escaped the notice of naturalists; but it does not appear that they have ascertained from which of the various substances of the tree the reproduced buds derived their origin.

After noticing some erroneous opinions respecting the origin of buds, Mr. Knight proceeds to relate some observations and experiments made by him on this subject. If the fruit-stalks of the Sea Cale (Crambe maritima) are cut off in the spring, the medullary substance decays, and a cup is formed, the sides of which consist of a woody substance, perfectly similar to the alburnum of trees. From the interior part of this substance, new buds are frequently generated in the ensuing spring: hence it is obvious, that the buds, in this case, do not spring from the bark; but it is not equally evident that they do not spring from some remains of the medulla.

In the autumn of 1802, Mr. Knight discovered that the potatoe possessed a similar power of reproducing its buds; which buds sprung from tubers generated on the surfaces made by the knife in dividing the root. In a former paper he has given some reasons for supposing that the internal substance of the potatoe is alburnous : he now observes, that there is in the young tuber a transparent line through the centre, which is probably its medulla; and that the reproduced buds did not spring from the central part, nor from the surface in contact with the bark, but from what he has supposed to be the alburnum of the root.

The author now gives an account of the experiments made, in the autumn of 1802, on young apple, pear, and plum trees, raised by him from seed, and, at that time, about two inches above the ground. These plants, after removing some of the soil, were cut off, about an inch below where the seed-leaves formerly grew; so that a portion of the root, about an inch long, and without any bud upon it, remained exposed. In the beginning of April, many small elevated points were seen on the bark; these appeared to proceed from the alburnum, and, as the spring advanced, perforated the bark, and produced shoots.

As it might be supposed that in the preceding experiments the buds may have originated from the medulla, Mr. Knight thought it right to make some similar experiments on old trees; and found the buds were reproduced by such trees, exactly in the same manner as by the annual roots.

Mr. Knight, in a former paper, has remarked, that the central

vessels appear to derive their origin from the alburnous tubes; he now thinks it not improbable that the lateral, as well as the terminal orifices of the alburnous tubes, may possess the power of generating central vessels, and that these vessels give existence to the reproduced buds and leaves.

Mr. Knight attempted to discover in seeds a similar power to regenerate their buds; but no experiments he could make were decisive, as he was never able to satisfy himself that all the buds could be eradicated without the base of the plumula being destroyed.

The power of reproducing buds here treated of, is not possessed, Mr. Knight says, by annual or biennial plants; but he relates that a turnip, from which the greater part of its fruit-stalks had been cut off, and of which all the buds had been destroyed, remained some weeks in an apparently dormant state; the first seed in each pod then germinated, and, bursting the seed-vessel, seemed to perform the office of a bud and leaves to the parent plant during the short remaining term of its existence.

Mr. Knight takes this opportunity to correct an inference drawn by him, in a former paper, from an experiment in which, after inverting a shoot of a vine and removing a portion of its bark, more new wood was generated on the lower lip of the wound, now become uppermost, than on the opposite lip. He has there inferred, that this effect was produced by sap which had descended from the leaves above. But as the branch was employed as a layer, the matter which would have accumulated on the opposite lip of the wound had been expended in the formation of roots; a circumstance which, at that time, escaped Mr. Knight's attention.

Some Account of two Mummies of the Egyptian Ibis, one of which was in a remarkably perfect State. By John Pearson, Esq. F.R.S. Read June 13, 1805. [Phil. Trans. 1805, p. 264.]

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After some general observations on the art of embalming, as it was practised by the ancient Egyptians, and on the various kinds of animals embalmed by them, Mr. Pearson proceeds to give a particular description of the very perfect mummy of an Ibis, which forms the chief subject of the present paper.

This mummy was taken out of the catacombs at Thebes, by the late Major Hayes, in the year 1802 or 1803. It was enveloped in cloth, and contained in an earthen jar, similar to those which are found at Saccara. Upon unrolling the bandage with which the mummy was covered, it was found to consist of strips of cloth, about three inches broad, which were strong and firm. The first circumvolutions of this cloth separated easily; but as the work proceeded, they were found to adhere more firmly, and at last were so closely united, that it was necessary to divide them by means of a strong knife. Each layer of cloth seemed to have been imbued with some bituminous substance in a liquid state; and the bandages were further secured by means of thread, in such a manner that the whole mass

was rendered firm and coherent; when the bandage was removed, the bird appeared to be covered with the same kind of bituminous substance that had cemented the strips of cloth. As much of this substance as could be removed without injuring the bird was now carefully taken off; and after the labour of several hours, Mr. Pearson succeeded in displaying the whole bird as it had been originally deposited by the embalmer.

The neck of the bird was twisted, so that the vertex of the head lay a little to the left of the sternum. The bill descended between the feet, and reached to the extremity of the tail. The feet were bent upwards, and placed one on each side of the head. The wings were brought close to the sides of the body. The feathers of the back and wings were white, tipped at their extremities with dark brown. The tail feathers could not be sufficiently cleared from the bituminous substance, to determine their colour. From the state of the quills of the wing feathers, it appeared that the bird had attained its full growth.

The dimensions of this bird were as follows:

From the termination of the neck to the extremity of

the tail...

Length of the neck

head and bill

metatarsal bone

inches.

124

8

4

sternum

Longest toe...

Width at the shoulders

Circumference of the body

Weight of the whole, 16 ounces, Troy.

13

No particular marks of decay can be perceived in this mummy, although it is probable, Mr. Pearson says, that the greater part of 3000 years has elapsed since it was embalmed. It was, he thinks, immersed in the bituminous matter, while that matter was in a liquid state; but that it was not boiled therein, as Grew supposed, is evident, from the feathers not being corrugated, or otherwise materially changed from their natural state.

Mr. Pearson unrolled another mummy of an Ibis, also sent from Thebes by Major Hayes, which appeared to have been embalmed in a different manner. The cloth of this latter was of a coarser texture; it had not been so thoroughly imbued with bitumen, nor were the circular bands continued to the body of the bird, which was merely wrapped in several pieces of cloth. This mummy was in such a state of decay, that no remains of the head or bill could be discovered. The exterior layer of feathers was in general of a dark colour, some of them tipped with white. The plumage of the neck and tail was white; the latter had a tufted appearance.

Whether the two birds here described were what authors have called the white and the black Ibis, Mr. Pearson cannot, he says, presume to determine. With respect to the mode in which such birds were embalmed, it appears, he thinks, contrary to what is

stated by Herodotus to have been the practice in embalming human bodies, that the stomach and intestines were not removed, as upon examining the interior parts of the last-mentioned Ibis, Mr. Pearson met with a soft spongy substance, containing several scarabæi in an imperfect state. These, he supposes, had been taken as the food of the bird, and were not digested at the time of its death. He also observes, that as larvæ of dermestides and other insects have been detected among the dust and bones of the mummy of an Ibis, it may be presumed that this bird was not always in a fresh state at the time when it was embalmed.

Observations on the singular Figure of the Planet Saturn. By William Herschel, LL.D. F.R.S. Read June 20, 1805. [Phil. Trans. 1805, p. 272.]

Notwithstanding the variety of extraordinary phenomena already observed respecting the planet Saturn, there remains, Dr. Herschel says, a singularity which distinguishes the figure of Saturn from that of all the other planets.

He had, in the year 1776, observed that the body of Saturn was not exactly round, and had found in the year 1781 that it was flattened at the poles, at least as much as Jupiter. In the year 1789 he measured the equatorial and polar diameters, and supposing there could be no other particularity in the figure of the planet, ascribed a certain irregularity he perceived in other parts of the body, to the interference of the ring.

Dr. Herschel now relates a series of observations made in the months of April, May, and June, of the present year, of which the following are the most remarkable.

April 12.-The flattening of the polar regions appeared not so gradual as in Jupiter, and seemed not to begin till at a high latitude. April 18.-The situation of the four points of the greatest curvature was measured with Dr. Herschel's angular micrometer, power 527. Their latitude was found to be 46° 38'; but as neither of the cross wires could be in the parallel, no great accuracy, Dr. Herschel says, could be expected.

April 19.-Ten-feet reflector, power 400. The figure of Saturn was somewhat like a parallelogram, with the four corners rounded off deeply. A measure of the position of the four points of the greatest curvature, taken this night, gave their latitude 45° 44'5.

May the 5th, 12th, and 13th.-Ten-feet reflector, with different powers. Jupiter and Saturn were viewed alternately, and compared. A greater curvature was evident at the polar and equatorial regions of Jupiter than at those regions in Saturn. These alternate observations were many times repeated, and the oftener the planets were compared, the more striking appeared the difference in their shape. May 26.-Ten-feet reflector, power 400. The difference in the three diameters of Saturn was evident without measurement. That which passes through the points of the greatest curvature being the

largest; the equatorial diameter the next; and the polar diameter the smallest.

June 1. Two measures of the latitude of the greatest curvature were taken, by setting the fixed thread of the micrometer to the direction of the ring. The mean of these was 43° 20'.

June 2nd. The two planets were viewed alternately, with powers of 300, of 200, and of 160; and even with the lowest of these, the difference in the figure of the planets was very evident.

The telescopic appearance of Saturn was then compared with a figure drawn from the measures Dr. Herschel had taken, combined with the proportion between the equatorial and polar diameters determined in the year 1789. From these a corrected figure was formed, of which an exact copy is given. The dimensions of it, in proportional parts, are,—

Diameter of the greatest curvature
Equatorial diameter

Polar diameter

Latitude of the longest diameter

36

35

32

43° 20'

These observations, Dr. Herschel thinks, may tend, in some measure, to ascertain the quantity of matter in the ring and its solidity; they also afford a new instance of the effect of gravitation on the figure of planets; for in the present case the opposite influence of two centripetal, and two centrifugal forces, must be considered.

On the magnetic Attraction of Oxides of Iron. By Timothy Lane, Esq. F.R.S. Read June 20, 1805. [Phil. Trans. 1805, p. 281.]

Mr. Lane having observed that hardened iron is not so readily attracted by the magnet as soft iron, was proceeding to make some experiments on the subject, when he was led, by Mr. Hatchett's paper on Magnetical Pyrites, &c., to examine what magnetical properties iron possessed when free from inflammable matter. For this purpose he procured some of the precipitate sold at Apothecaries' Hall under the name of Ferrum precipitatum, and which is prepared by adding purified kali to a solution of sulphate of iron. This precipitate, the author says, has no magnetic particles; nor, when exposed to a clear red heat, does it acquire any, except when smoke or flame have access to it. The solar heat, when concentrated to the degree at which glass melts, does not render this oxide magnetic, provided it be protected by glass from the dust floating in the air; if not so protected, many of the particles become magnetic.

Mr. Lane then rubbed various portions of the oxide, in a glass mortar, with different combustible substances, namely, coal, sulphur, charcoal, camphor, ether, alcohol, &c., but found the oxide was not thereby rendered magnetic, without the assistance of a degree of heat equal to that of melting lead; with that degree, however, it became magnetic. Hydrogen, when aided by a red heat, had the same effect. Charcoal and cinders, well burnt, were found to require a longer continuance of the heat, to have their full effect on

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