greater elevation than the second, its progress was for a time interrupted, leaving the spectators in doubt which direction the second storm would take. It was evident from their mutual repulsion, that the two clouds were charged with the same electricity, and the consequence, as might be expected, was a combat in which the earth took an important part. Hitherto, thunder had been heard to proceed from the second storm, when suddenly one of the lower clouds descended towards the earth, and came in contact with it, and all explosion appeared to cease. A prodigious attraction took place; all the light bodies, all the dust which covered the surface of the ground, rushed towards the point of the cloud; a continual rumbling noise was heard; small clouds were whirled about the inverted cone, ascend. ing and descending rapidly. An intelligent observer, M. Dutour, being favourably placed, saw the cone terminated at the lower extremity, by a calotte, or cap of fire; but a shepherd, Olivier, who was on the spot, saw nothing of the kind, ow. ing to the torrent of dust in which he was enveloped. The trees situated at the S. E. of the trombe were partially attacked on the N.W. side; those parts underwent a sudden and very remarkable alteration (which will be described hereafter), while the other portions of the same trees, preserved their sap and vegetation. The trombe descended the valley at the extremity of Fontenay, following the direction of a row of trees, planted along the banks of the bed of a rivulet without running water, but wet at bottom; then, after having broken and rooted up all it encountered, it crossed the valley, and advanced towards other plantations on the opposite hill, and destroyed them likewise. There it stopped several minutes, as if uncertain in which direction to proceed. It had arrived under the limits of the first storm, which had hitherto remained stationary, but now began to agitate itself, and retire towards the valley to the west of Chatenay. The trombe which remained upon the plain of Thibault, would infallibly have taken the direction of a wood to the westward, if the first storm had not prevented it by its repulsion. After having dried up, overturned, and destroyed all the plain of Thibault, the trombe advanced towards the park of Chatenay Castle, overturning everything it met with in its passage. Arrived in the park, it converted one of the most agreeable habitations in the environs of Paris, into a place of utter desolation. The park has lost all its old trees; some young ones at the extremity, and beyond the action of the trombe, have alone escaped destruetion. The walls are thrown down; the mansion and the farm-house have lost their roofs and chimneys; the trees were carried away several hundred metres; fragments of wood and tiles from the buildings were projected to the distance of more than 500 metres. The trombe next descended the hill towards the north; it remained some time over a pond, broke down and dried half the trees, and killed all the fish. It then proceeded slowly along an avenue of willows, whose roots were in the water; during this passage it lost a great part of its extent and violence; it continued to move still more slowly over an adjoining plain for about 100 metres, when it separated into two parts, one portion rising as a cloud, and the other dispersing itself on the ground. All the trees struck by the trombe, presented the same appearance; all their sap was evaporated, the wood alone remaining, almost entirely deprived of its cohesion; it was as dry as if it had remained 48 hours in an oven heated to 150°; no vestige of humidity could be perceived. This immense quantity of vapour instantaneously formed, could only escape by bursting the tree; and as the ligneous fibres are less cohesive in the horizontal than in the longitudinal direction, the trees were in some instances literally split into laths. Fifteen hundred trees bear marks which prove that they have served as conductors to masses of electricity; that the great elevation of temperature caused by the electrical flood, instantly vaporized all humidity in these vegetable conductors; that this vaporization caused the trees to split longitudinally; that the trees so dried and split became bad conductors, and would no longer afford a passage for the fluid; and as they had lost their cohesive force, the violence of the trombe broke them, instead of tearing out their roots. By following the progress of this pheno menon, we may observe the transformation of an ordinary storm into a trombe, which is designated whirlwind, or waterspout, according as it descends on the land, or on water; and we are thus led to conclude, that the trombe is but a nebulous conductor, serving as a passage for the continual discharges from more elevated clouds. The only difference between an ordinary storm, and a storm accompa nied with a trombe, is the addition of a conductor which directs the combat of a whole storm upon the points situated beneath the lower extremity of the cone. Butterflies. The Butterflies in foreign countries, are far more numerous, and much more remarkable for their size and beauty, than any in Britain. Lander, in his travels in Africa, says, "There was one beautiful sight which we cannot but mention, an incredible number of butterflies fluttered about us like bees. They were variegated by the most brilliant tints. The wings of some were of shining green, edged and sprinkled with gold; others were of sky blue and silver; others of purple and gold, delightfully blending together; and the wings of some were like dark silk velvet, trimmed and braided with lace." On another occasion he says, "Millions of butterflies fluttered around us, and literally hid from our sight, every thing but their own variegated and beautiful wings."-Juvenile Naturalist. INSTITUTIONS. LECTURES DURING THE WEEK. London Mechanics' Institution, 29, Southampton, Buildings, Chancery-lane. Wednesday, Aug. 7, E. Cowper, Esq., on the Pottery and Porcelain Manufacture. At half-past eight precisely. Westminster Literary and Scientific Institution, St. Pancras Literary and Scientific Institution, QUERIES. I should be glad if one of your correspondents has a small lathe to dispose of, and if so, at what price. N. P. R. Rain.-"The approach of the rainy season," says one who lived in India, " is generally announced by vast masses of clouds that rise from the Indian ocean, and advance towards the north-east, gathering and thickening as they come near the land. After some threatening ing wainscot, and how are they mixed? How to silver common glass? How to make days, the sky assumes a troubled appearance in the evening, and the monsoon generally sets in during the night. It is attended by thunder storms far exceeding those in more temperate regions. It generally begins with violent blasts of wind, which are succeeded by floods of rain. For some hours, lightning is seen almost without intermission; sometimes it only illuminates the sky, and shows the clouds near the horizon; at others, it discovers the distant hills, and again leaves all in darkness; when, in an instant, it re-appears, in vivid successive flashes, and exhibits the nearest objects in all the brightness of day. During all this time, thunder never cesses to roll; and is only silenced by some nearer peal, which bursts on the ear with such a sudden and tremendous crash, as can scarcely fail to strike the most insensible heart with awe. At length, the thunder ceases, and nothing is heard but the continued pouring of the rain, and the rushing of the rising streams. The next day presents a gloomy spectacle; the rain still descends in torrents, and scarcely allows a view of the blackened flelds; the rivers are swollen and discoloured, and sweep down along with them the hedge, the huts, and the remains of the cultivation which was carried on during the last dry seasons in their beds." gold size for gilding picture frames, and the process for burnishing mouldings of picture frames? What are the ingredients for grain J. B. To solve by means of Euclid, entirely without the use of trigonometry, the following:-" Ou the sides of any plane triangle equilateral triangles are described, to prove that the lines joining the centres of these three equilateral triangles, form also an equilateral triangle? G. H. ROLLS. ANSWERS TO QUERIES. To make Soda-water.-Take 40 grains of carbonate of soda, put it into a common soda-water bottle nearly full of water; immediately afterwards put into the same, 35 grains of tartaric acid, then cork it quickly. The acid and the soda ought to be put in in crystals, as when in before the bottle can be well corked, and so a conpowder, they are apt to seize upon each other siderable quantity of the carbonic acid gas which is evolved is lost. In the above progress, the tartaric acid having a greater affinity for the soda than the carbonic acid gas has, combines with it, and forms the tartarate of soda. By this combination, the gas which was engaged with the soda is evolved, or set free, and mixes with the water in the bottle, and makes its escape when the cork is withdrawn. To make Lemonade Powders.-Forty grains of tartaric acid, 30 grains of carbonate of soda, a few drops of essence of lemon to suit your taste, and half an ounce of loaf sugar. To make Ginger Beer Powders.-A most animating method of making ginger beer, is given at page 270, Vol. II., of the "Penny Mechanic." To Dye Ivory Scarlet.-Make a ley of wood ashes, of which take two quarts; pour it in a pan upon a pound of Brazil wood, to this add two pounds of copper filings, and one pound of alum; boil the whole half an hour, then take it off and let it stand; into this put the ivory, and the longer it continues in this liquor, the redder it will be. The same process and dye will do for bone, and make either of a tine coral red. To make Rocket Cases.-By your magazine of the 20th July, I see your correspondent" Publico" is desirous of knowing how to make rocket cases, and I shall feel great pleasure in informing him how to do so through the medium of your magazine; but at the same time I would inform him, that unless he has three essential things necessary towards making rockets, viz., time, patience, and a great deal of money, I would dissuade him from it, as I can assure him, it is a very arduous undertaking. A. M. To remove Hair from the Skin.-I beg to inform "Tyro," that hair may be removed from the face and hands by using a compound called the "Oriental Russua." To form this, mix two ounces of quick lime with half an ounce of orpiment, or realgar (sulphuret of arsenic); boil that mixture in one pound of strong alkaline lye; then try its strength by dipping a feather into it, and when the flue falls off, the russua is quite strong enough. It is applied to the skin by a momentary friction, followed by washing with warm water. Its This should be used with the greatest care, beginning with it somewhat dilute. causticity may be tempered by the addition of one-eighth of starch or rye flour. To Silver Brass.-" Tyro." The white curd obtained by adding a solution of common salt to one of nitrate of silver, is to be well washed and dried; one part of this powder is to be mixed with three of good pearlash, one of washed After clearwhitening, and one half of sea salt. ing the surface of the brass, it is rubbed with a piece of soft leather, or cork moistened with water, and dipped in the above powder. After the silvering, it should be thoroughly washed with water, dried in saw-dust, and immediately varnished. Some use a mixture of one part of the silver precipitate with ten of cream of tartar, and this mixture answers very well. JUVENILE ENTERTAINER. Another Method.-" Tyro," may silver brass of any description, by rubbing over it a solution of nitrate of silver, which may be prepared in the following manner:-Half an ounce of silver; three quarters of an ounce of nitric acid; put the silver to the acid, and when the solution is complete, add one ounce of rain-water; then rub the solution on the brass (previously well cleared), and the silver will adhere to it, after which, polish it with soft leather. J. MITCHELL. How to make Diamine Ink. N. Carter." The diamine ink is, I believe, a preparation of the black oxyde of manganese; and as I have made a very excellent ink with the manganese, which is not susceptible of being effaced with chlorine, I submit the following formula:-Boil one ounce of Brazil wood with half an ounce of alum in twelve ounces of water, and continue the ebullition till the liquid shall have been reduced to eight ounces; then add one ounce of the black oxyde of manganese, reduced to an impalpable powder, and with it half an ounce of gum Arabic. To Stain Paper.-" Publico, of Manchester," may stain paper a pink colour, by infusing an ounce of Brazil wood and half an ounce of pearlash in one pint of boiling water, and letting it infuse for two hours, then straining it, and apply it with a sponge. J. MITCHELL. TO CORRESPONDENTS. A. D. M.-The method of preventing the dry rot by boring holes at the bottom of the trunk, to kill and drain the tree before it is felled, was described in a recent number of the "Mechanic." We shall be glad to receive the papers on optical instruments. N. P. R. will find an article in our present number, which will answer his query; but the mode of silvering copper there described, is not well suited to articles exposed to handling, as it will soon wear off. There is no process of silvering at present known, which will deposit a coat of silver of any considerable thickness, except by tedious and difficult operations, which are only applicable to particular cases. W. G. A. H.-The subject of his communication respecting the Leyden phial, was ably described in a recent number of the " Mechanic," by our talented correspondent "Electron." Experimentalist.-Faded flowers may be restored by inserting the stalks in boiling water. NEW WORK (To be completed in Twenty Monthly Numbers), price 6d. This Day is Published, the Second Edition of No. II. of WILL'S WHIM; consisting of Characteristic Curiosities, with Original Anecdotes of Men and Things. Illustrated by Jacob Parallel, Esq. PLAN OF THE WORK. Every Number will exhibit the Virtues, Vices, or Follies, of Human Life, as they every day appear, in their most Of such amiable, most subtle, or most eccentric forms. characters, however, those only will be selected as, it is presumed, will afford a pleasing interest in the perusal of their actions, from their respective peculiarities in attaining their favourite objects. In addition to our other details, we shall occasionally diverge into the very depths of drollery of every denomination. The not unfrequent comie tragedies of real life, the burlesque of intuitive discovery, the epicurean sentimentalities of modern refinement, are all fair game for the goose quil; and in pursuit of which, while we hope to prove ourselves good marksmen, we will only premise here, that it shall be our special aim never to overshoot the mark. With each Number will be given, in addition to our Mustrations of comicalities, cut in wood, an elegant Steel Engraving. We shall sedulously persevere in our self-imposed task, until "Will's Whim" shall constitute a handsome octavo volume; and which, when completed, is intended to be the most amusing record of exemplification extant. London: G. Berger, Holywell-street, Strand; and D. A. Doudney, 1, Long-lane, Smithfield. London: Printed at "THE CITY PRESS," 1, Long Lane, Aldersgate, by D. A. DOUDNEY (to whom all communications for the Editor must be addressed, postage paid); published every Saturday, by G. BERGER, Holywell-street, Strand: and may be had of all Booksellers and Newsmen in Town and Country. WOOD AND SHARWOOD'S LITHO- | to, you will excuse my taking this means to inform the Mining Journal, that the question of making locomotive engines of the kind which led to the "conditional order," was discussed with two makers of celebrity in this country in the first instance, and it was not until they had declined to undertake an order that a negociation was set on foot with an American engineer. The Mining Journal appears to give credit to the Directors for having obtained a good article, but appears to be dissatisfied with the further course pursued by those gentlemen, viz., to procure duplicates of the same good article under like conditions; and in preference, it advises that the Directors should endeavour to procure uncertain imitations of the article. Under the above explanation, I hope it will appear that the course pursued was neither so improper nor so injudicious as the writer of the article in question would seem to imply. I am. Sir, yours faithfully, W. S. MOORSOM, Engineer. Worcester, 26th July, 1839. ADAMS'S PATENT CARRIAGE IT has been affirmed that Mr. Adams's A SHORT time back, we published an article on this subject, in which it was stated, on the authority of the Mining Journal, that the directors of the Birmingham and Gloucester Railway had contracted with an American manufacturer for the supply of engines; the truth of that statement, we are sorry to find, is fully confirmed by a communication from the engineer, captain Moorson, to the "Railway Times" of last Saturday. We insert that letter, as it is intended for a defence; but we cannot help remarking that it is very strange indeed that America should so suddenly have surpassed England in the manufacture of machinery, for which this country has hitherto been so pre-eminent. The "Having been given to understand that "Railway Times" appears perfectly sa- an opinion, or rather notion, is rife amongst tisfied with the explanation; and we are many persons connected with railroads, sorry that we cannot join our contempo- that the safety of the patent bow-springs rary in excusing the transaction. If the in use on the London and Birmingham legislature were to interfere to prevent the line, is not commensurate with their ac importation of foreign engines, the direc- knowledged ease of motion, I ask the fators of the Birmingham and Gloucester vour of a short place in your columns, to Railway Company (the only one in Eng-show the fallacy of such a notion, and the land which cannot procure suitable engines in this country), would, no doubt, soon recollect the address of some manufacturers who could supply them. Captain Moorson's letter is as follows: “Sir,—I have observed in your journal of the 20th instant, an article extracted from the Mining Journal, headed, "Encouragement to Engineers," which seems in some degree to reflect upon the Directors of the Birmingham and Gloucester Railway, in consequence of their having given a "conditional order" for some American engines. As I have borne a principal share in the recommendation by which the Directors have come to their own conclusion on the occasion referred source from whence it has arisen. The spring in common use acts merely as a cushion between the body and axle, its motion is very small, and it provides only for vertical shocks. It has no attachment to the vehicle, and consequently grooved guards are provided, firmly bolted to the frame-work, and in which the axle box slides up and down, much as an oar is retained by the thole pins of a boat. If the spring were to break, the axle would still retain its position of traction. In the patent bow-spring, the axle guards are dispensed with, and therefore unscientific persons deem that the security is lessened. But mechanicians who examine carefully will find, that the security |