presented as a common shrub in Nipal, producing large panicles of blood-red blossoms. Almost all the foregoing, surpassing as is the loveliness of some of them, are eclipsed by the Bignonia multijuga, tab. 95 and 96, a large forest tree found on the mountains of Sylhet, bearing immense woody panicles of flowers resembling those of the common Catalpa. And, finally, Begonia pedunculosa, tab. 97, is a lovely little herbaceous plant, which seems, from its stems and leaves, as if nature had intended them all for flowers.

We learn, from the preface, that this work appears under the immediate patronage of the East India Company; we congratulate the author that he has such patrons, and the Company that they have such a servant.

We have already stated that the second part of the Company's plan was that of distributing throughout the whole scientific world the immense collections which they had caused to be formed at such great charge to themselves, and such incredible personal exertion on the part of their civil servants. The whole of the details of executing this gigantic scheme were of course entrusted to Dr. Wallich, who judiciously adopted exactly the mode that would be most agreeable to a liberal-minded man. He invited all the botanists of Europe to co-operate with him in his enterprise, offering one tribe to this, and another to that person, taking care that in all cases the different families should be placed in the hands of those who were known by their published works to be best acquainted with them. What has been the effect? England has seen the learned men of Germany, Russia, and France, repairing to her shores to assist in this splendid project, and those of all nations enrolling themselves in the list of contributors to the noble enterprise of the British East India Company; she has beheld men of all parties, of all countries, concurring in the prosecution of it, and the great lords and princes of the land supporting it by their countenance and assistance.

May the example of the British East India Company, in regard to the collections of the Botanic Garden, Calcutta, be followed in all the public establishments of the United Kingdom, and in every department of their own! May the guardians of our national institutions direct a similar application to be made of the objects of science in their possession; and may our public functionaries destroy for ever, the pernicious practice of collections formed at the expense of the public purse, and by the authority of the British government, serving no other purpose than that of exclusively augmenting some single collection!

The second work at the head of this article is a numerical catalogue of the species that are thus distributed by the East India Company.

FOREIGN AND MISCELLANEOUS INTELLIGENCE.

§ I.-MECHANICAL SCIENCE.

1. ON THE DISCHARGE OF A JET OF WATER UNDER WATER.(R. W. Fox, Esq.)

THE following letter is addressed to the Editors of the Philosophical Magazine.

I am not aware that it has been before noticed, that a jet of water discharges the same quantity, in water, as in air, in a given time, without reference to the depth or the motion of the water, at least within certain limits. Thus when the experiment was tried with a head of water six feet high, the same orifice discharged equal quantities in equal times, in air, in still water, and in a rapid stream, moving at the rate of about six feet in a second; the jet having in one case been turned with the current, and in another against it: and when, by lengthening the tube, the aperture was submerged to the depth of fifteen feet, the effect was the same as at the surface, under the pressure of an equal column above it. These results have been obtained by my brother Alfred Fox and myself, and you may perhaps think them deserving a place in your Magazine, if they should appear to you to be new.

We sometimes coloured the water, when the jet appeared to pass unbroken to a considerable distance under the water *.'

2. ON PREVENTING THE DISCHARGE OF A BULLET FROM A GUN BY THE FINGER.

At the sitting of the Helvetic Society of Natural Sciences of the 28th July last, a letter was read from Dr. Flachin of Yverdun, relative to an experiment before mentioned to the society, in which the ball was prevented from leaving the bottom of a musket when the gunpowder was fired, simply by putting the ramrod upon the ball, and the end of the finger upon the ramrod. He supposes the effect may be explained by the circumstance, that near the charge the ball has a very small velocity compared to that impressed upon it by the expansive force of the gases from the fired gunpowder, when exerted during the whole of the time in which it is passing along the barrel. It is well known that the effect thus accumulated is the reason why long pieces carry further than short ones, and why the breath of a man, which cannot exert a pressure of more than a quarter of an atmosphere, may, by means of a tube, throw a ball to the distance of sixty steps. The experiment above requires great care, especially as to the strength of the piece, which is very liable to burst in the performance of the experiment †.

*Vol. yiii, p. 342.

Bib. Univ., 1830, p. 447.

3. CLEMENT'S EXPERIMENT-EASY MODE OF REPEATING IT. The very curious, and apparently paradoxical experiment, first described by Clement, in which air, gas, or steam, issuing with force from a hole in a flat surface, did not blow away a platter or other flat and extended body, but rather caused its adhesion, has been repeated since in a great variety of forms. M. Hachette contrived a simple little apparatus, by which every one was put in possession of the power of witnessing the effect: and such facilities are valuable, because they rapidly extend the knowledge of curious effects, and cause them to be still more extensively pursued and investigated. The experiment may be still further simplified in the following manner. When the fingers of the open hand are retained as close to each other as they can be, still there are certain slit-like intervals between them extending from joint to joint. Let the hand be held horizontally with the palm downwards, apply the lips to the interval between the second and third fingers nearest to their roots, and then blowing with force, a strong jet of air will of course issue from the aperture at the under side of the hand. Now, put a piece of paper or a card three or four inches square against that aperture, and again blow; it will be found that the paper will neither be blown away, nor fall by its own weight, but will be pressed upwards against the hand and the issuing current of air, so long as that current continues. The moment it ceases, the paper will fall away by its own gravity, in obedience to the ordinarily active laws of nature.-M. F.

4. BROWNE'S MOVING MOLECULES.

Muncke, of Heidelberg, finds the following a simple and easy mode of showing the motions of particles ;-triturate a piece of gamboge the size of a pin's head in a large drop of water on a glass plate; take as much of this solution as will hang on the head of a pin, dilute it again with a drop of water, and then bring under the microscope as much as amounts to half a millet-seed;-there are then observable in the fluid small brownish-yellow points, generally round (but also of other forms), of the size of a small grain of gunpowder, distant from one another from 0.20 to 1 line. These points are in perpetual motion, varying in velocity, so that they move through an apparent space of 1 line in from 0.5 to 2 or 4 seconds. If fine oil of almonds be employed in place of water, no motion of the particles takes place, but in spirit of wine it is so rapid as scarcely to be followed by the eye. This motion certainly bears some resemblance to that observed in infusory animals, but the latter show more of voluntary action. The idea of vitality is quite out of the question. On the contrary, the motions may be viewed as of a mechanical nature, caused by the unequal temperature of the strongly illuminated water, its evaporation, currents of air, heated currents, &c. If the diameter of a drop be 0.5 of a line, we obtain, by magnifying 500 times, an apparent mass of water of more than a foot and a-half

broad, with small particles swimming in it; and if we consider their motions magnified to an equal degree, the phenomenon ceases to be wonderful, without, however, losing anything of its interest *.

5. EXACT MEASURE OF A DEGREE.

Ten thousand rubles (upwards of 15007.) a year have been granted by the Emperor of Russia for the continuation of the investigations undertaken to obtain the exact measure of a degree. This work, which, it is said, will last for ten years, is confided to the charge of M. Struve, of Dorpat. Two staff officers, natives of Finland, Messrs. Rosenius and Aberg, are already gone to their country for the purpose of discovering the mathematical points of union between Hochland and Tornea. M. Struve has projected a journey abroad, in furtherance of this great undertaking †.

6. SVANBERG ON THE TEMPERATURE OF THE PLANETARY SPACE.

M. Fourier obtained, as one of the results of his important investigations of the temperature of the earth, &c., that the temperature of the planetary space was equal to -50° C., or (-58° F.), and arrived at the conclusion also, that the earth has arrived at its lowest degree of temperature, or that point below which it could not sink. M. Svanberg has arrived at a result so nearly the same, as to be very remarkable, especially considering that his mode of investigation was altogether of a different nature, and had for object atmospherical refraction. He wished to examine completely the problem of atmospherical refraction, and also the various hypotheses which have been put forth to determine its quantity. Some of these appeared sufficient for astronomical purposes, but having concluded their investigation, M. Svanberg wished to view the subject in a physical point of view, and then arose the difficulty of being able to determine, for each temperature observed at the surface of the earth, the law of the corresponding distribution of heat in the atmosphere, under the hypothetical condition of perfect equilibrium, and also the law according to which the temperature diminishes at different elevations above the level of the sea.

"In this examination, as in others (says M. Svanberg) where a greater or smaller number of natural phenomena are to be subjected to a mathematical formula, great inconvenience occurs, from the circumstance that an infinity of functions of various forms are capable of representing a finite number of observations, and that the real accuracy of the formula adopted can only be judged of by the accordance which it presents with those observations which have not served for the determination of its constants, by the number and the nature of the observations to which they may apply. Hence it

* Jameson's Journal, 1830.

+ Bull, Géog. xiii. p. 306.

results, that one can never have a general rule by which to arrive directly at the point required, and that the work is obliged to be commenced with an hypothesis which, at a later period, is to be subjected to criticism from the observations. At the same time, the adoption of an hypothesis does not depend upon accident, but requires the most intimate knowledge of mathematical forms in their greatest extent, otherwise the progress would only be from error to error. One rule, however, should be observed-it is, to commence by trying those formula which require the determination of the smallest possible number of arbitrary constants.

• Guided by these considerations, and by the relation between light and heat so evident in the power which the solar rays possess of producing heat by their passage through bodies but little transparent, I commenced by supposing that the planetary space, with a perfect transparency, would undergo no change of temperature, neither by the effect of light nor radiant heat; and that therefore the elevation of temperature above that of the etherial regions can only commence at the limits of the atmospheres of the planets. A necessary result is, that the rate of change of temperature at a height infinitely above the surface of the earth is always proportional to the rate of the corresponding change in the capacity which the atmosphere possesses of absorbing light. Upon these considerations I expressed the temperature of the atmosphere by means of a formula, which applies to any height above the surface of the earth, and which contains only two arbitrary constants; one, which is also a function of the time, is always determined by the immediate observation of the corresponding temperature of the surface of the earth; and the other, which does not vary in relation to time, is the temperature of the planetary врасе.

The numerical determination of these constants requires exact observations of the temperatures of isolated points, up to a considerable height above the earth's surface; but, unfortunately, these observations are so difficult, that at present I could take advantage of one only, that made by M. Gay Lussac, in his aërial voyage. It is very much to be desired that this observation should be repeated, especially in the neighbourhood of the equator, where atmospheric variations are small, and where, consequently, the influence of accidental circumstances are less to be feared. Nevertheless, the single observation of Gay Lussac has given me -49°.85 C., as the temperature of the planetary space, a number which only differs one-seventh of a degree from that obtained by M. Fourier, according to the laws of heat, radiating from the solid globe, supposed to have arrived at its state of fixed and invariable temperature.

'Without having much doubt as to the identity of light and heat, or as to the accuracy of our photometrical knowledge, I thought it would still be interesting to see the results which would be given by setting out from the data of Lambert, on the absorption of light, which, coming from the zenith, passes through the whole depth of the atmosphere: establishing my calculation on the supposition that