⚫dered an improvement on the cold affusion. Some clay is procured, and mixed with water, until it acquire the consistency of batter the patient is smeared all over his body with it; after an hour or two an examination takes place, and if the clay has become parched, and is peeled off, death is considered to be the inevitable result; but if it be cracked, and the pieces adhere to the body, a favourable result is expected. This is, most probably, the fruit of observation, as I believe the science of medicine among such people generally is; but the effect of the application in the latter case is a copious perspiration, which is absorbed by the clay, by which an adhesion to the cutis takes place, and prevents it from falling off: thus the experiment, if not at first founded on scientific principles, has been undoubtedly supported by practical facts. Stevenson's South America.

The Coca Tree. This is a small tree, with pale bright green leaves, somewhat resembling in shape those of the orange tree. The leaves are picked from the trees three or four times a year, and carefully dried in the shade; they are then packed in small baskets. The natives, in several parts of Peru, chew these leaves, particularly in the mining districts, when at work in the mines or travelling; and such is the sustenance that they derive from them, that they frequently take no food for four or five days, although they are constantly working. I have often been assured by them, that whilst they have a good supply of coca they feel neither hunger, thirst, nor fatigue; and that, without impairing their health,

they can remain eight or ten days and nights without sleep. The leaves are almost insipid, but when a small quantity of lime is mixed with them, they have a very agreeable sweet taste. The natives put a few of the leaves in their mouths, and when they become moist, they add a little lime or ashes of the molle to them, by means of a small stick, taking care not to touch the lips or the teeth; when the taste of the coca diminishes, a small quantity of lime or ashes is added, until the taste disappears, and then the leaves are replaced with fresh ones. They generally carry with them a small leather pouch, containing coca, and a small calabash, holding lime or ashes; and one of these men will undertake to convey letters to Lima, a distance of upwards of a hundred leagues, without any other provision. On such occasions they are called chasquis, or chasqueros, and this epithet is also given to the different conductors of the mails. The Incas had men stationed on all the principal roads for the transmission of any article belonging to the Inca, who, according to the quality of the road, had to carry it to different distances-some one league, others two, and others three. These men were continually employed, and when one of them arrived, he delivered to the one in waiting whatever he was charged with, and gave him the watch-word, chasqui; this man ran immediately to the next post, delivered his charge, and repeated chasqui; and then remained to rest until the arrival of another. By these means the court of the Incas was supplied with fresh fish from the sea.-Ib.

New Light. The interior of the

the theatre La Fenice, at Venice, is now lighted up by means of a new process invented by the mechanician Locatelli. It appears, from the description given of it by an Italian journal, that lamps concealed in the roof and fitted up with parabolic reflectors, throw all their rays of light upon an opening one foot in diameter, in the centre of the ceiling. This opening is furnished with an ingenious system of lenses, which concentrate the rays and reflect them to every part of the house. This mode of lighting presents several advantages; the light is more vivid and more generally diffused; nothing intervenes between the stage and the spectators occupying an elevated situation in front; the lamps may be approached to be trimmed without the public perceiving it; and there is neither smoke nor smell proceeding from the burning of oil. An idea of this method may be formed by representing to oneself a luminous disk on the sun at its zenith.

Composition of an Ink similar to China Ink.-Take six parts of isinglass, which are to be dissolved in double their weight of boiling water; in like manner, dissolve in two parts of water one part of Spanish liquorice; mix the two liquors warm, and gradually incorporate with them, by means of a wooden spatula, one part of the best ivory black. When this mixture is properly made, it is heated in a water-bath, that the whole of the water may be evaporated. The requisite form is then given to the paste which remains. The colour and goodness of this ink are equal to those of the true China ink.--Jameson's Ed. Jour.

Antidotes to Poisons.-Mr. J. Murray, in a paper in Brewster's Edinburgh Journal of Science, just published, after detailing a number of experiments on frogs, rabbits, &c., says, “I have no hesitation to pronounce with most positive certainty, that in ammonia will be found a complete antidote to hydrocyanics (or prussic) acid, and in acetic acid an effectual counter-poison to opium."

Barometers." Mr. Daniell has found that air insinuates itself into the vacuum of the best made barometers, in time, by creeping up between the mercury and the glass, and that it will insinuate itself between any fluid and any solid, when it has not attraction enough for the former to cause it to wet it. If any gas be confined in a glass jar for a length of time over mercury, it will make its escape, and its place be occupied by atmospheric air; whereas the same gas, if confined by water, will be preserved unmixed. Hence the best made barometers are often studded with air bubbles. The cure which Mr. Daniell has provided for these evils is to weld a narrow ring of platinum to the open end of the tube, which is immersed in the cistern. Boiling mercury amalgamates itself with platinum, and adheres to it when cold, wetting it, but not dissolving it; so that, by this means, the passage of the air is cut off as effectually as if the whole tube were wetted by it.-Shumacher's Astronomical Nachrichten."

Pectic or Coagulating Acid.This new acid has been discovered by M. H. Braconnot, and receives its name from TEKTI, coagulum, in consequence of its resembling a jelly or gum. It is found in all

vegetables.

vegetables. It is sensibly acid. It reddens turnsole paper. It is scarcely soluble in cold water, but more so in hot water. It is coagulated into a transparent and colourless jelly by alcohol, by all the metallic solutions, by limewater, water of barytes, the acids, muriate and sulphate of soda, and nitre, &c. It forms, with potash, a very soluble salt, consisting of 85 parts of lead, and 15 of potash. This salt has the remarkable effect of communicating to large masses of sugar and water the property of gelatinising, which renders it of great use to the confectioner. Mr. Braconnot, in this way, prepared aromatised jellies, perfectly transparent and colourless, and very agreeable to the taste and the eye. He also made with rose-water, coloured with a little cochineal, rose-jelly of exquisite taste. Ann. de Chim."

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Somnolency. - The celebrated physician, Hufland, has caused the following paragraph to be inserted in a Berlin paper:- "A late paper has contained an account of an extraordinary instance of lethargic drowsiness, which lasted for a considerable time. A still more singular example of this disorder occurred within my observation, in a young girl of Nedebach, in Westphalia, who remained in a state of complete lethargy for 451 days. As this disorder appears to have become much more frequent than formerly in this country, I think it well to call the attention of the public to the effects of galvanism, as the best stimulant that can be employed in such cases."

Composition of Ancient Vases. -In No. XXV. of the Edinburgh Philosophical Journal, (Professor Jameson's,) we find the following:

1825.

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"Professor Hausman concludes an interesting disquisition on the composition of ancient Etruscan vases, with these results

"1. That the manufacture of earthen vases appropriated to fu neral occasions had been widely propagated at a remote period of antiquity, with little deviation from a general plan, in so far as regards their principal circumstances.

"2. That these vases have been formed with much particular diversity, in regard to less important circumstances, such as the quality of the clay employed, and differences in the forms, ornaments and paintings, not only in different countries and at different times, but also in the same countries, and at the same periods.

66

"S. That the finer sort of these vases are superior, in regard to the preparation of the clay, and the elegance and variety of the forms, as well as the ease of the paintings, to all others of the kind, whether of Roman or of modern manufacture; insomuch, that the pottery of the most remote ages forms the model of that of the present times.

"4. That the art of manufacturing those vases, as practised in very remote times, is much more worthy of estimation than our best performances in that way, since the ancients were not in possession of many assistances which are applied to the art by us, and because some things which are now done without difficulty, by means of certain instruments or machinery, were, in those times, perfected by means of the hand alone, by the greater dexterity of the artist.

"5. That certain circumstances were peculiar to the very ancient

G

art

art of making and ornamenting those earthen vessels, which have evidently been lost in later times; of which may be mentioned, in particular, the composition of a very thin varnish, which gave a heightening to the colour of the clay in a greater or less degree, and afforded a very thin, firm, black coating, retaining its lustre to the most remote ages, and capable of resisting the action of acids and other fluids; so that the modern art of manufacturing pottery-ware may be materially improved, not only with regard to the forms and ornaments, but also the preparation and application of the materials, by a diligent and continued examination of those very ancient vases."

Swallowing Insects. There is a curious account of a countryman, who suffered a long, severe, and debilitating illness, in consequence of having swallowed the larva of one of the dipterous tribes of insects, (Tipalidæ,) commonly called dragon flies, which haunt our ditches and stagnant pools. This larva, instead of being destroyed, had become a large hairy caterpillar in his stomach, and caused the disease, which was finally cured by its being ejected in a fit of vomiting. It is extraordinary, that animal life should have been preserved in such a situation; but Dr. Yule, who writes the paper, mentions the larva of a carniverous beetle, which not only lived, but moved briskly in strong alcohol. The ovo of many species are, indeed, almost indestructible.

Singular Eastern Custom.-In a paper, in Brewster's Edinburgh Journal of Science, by Dr. Govan, on the Natural History, &c. of the Himalayah Mountains, he states,

while at Nahan, which is from 3000 to 3200 feet above the level of the sea, and where the Croton is used for fences, "Here I first noticed the custom which has been frequently observed to prevail in these districts, of laying the children to sleep, apparently much to their satisfaction, at the commencing heats, and until the rainy season begins, with their heads under little rills of the coldest water, directed upon them for some hours during the hottest part of the day. Here it was practised in the case of a life no less precious than that of the young Rajah of Sirmoor, a boy about ten or twelve years of age, a sufficient evidence of the estimation in which the practice is held. It is most commonly, however, followed in the case of infants at the breast. The temperature of the water I have observed to be from 46° to 56° and

65°, and have only to add, that it seemed to me most common in those districts which, having a good deal of cold weather, are nevertheless subject to very considerable summer heats. It was a great preservative, the people affirmed, against bilious fever, and affections of the spleen, during the subsequent rainy months." Dr. Brewster relates the success of experiments which he had made, and from which he obtained excellent single microscopes, by disposing the lenses of fishes' eyes on silver paper. They last for several hours, and can very readily be replaced where occasion requires.

Professor Mitscherlich, of Berlin, furnishes a very able paper on the production of crystallized minerals by heat, from which the following important geological inferences are drawn:

"The

"The artificial production of minerals by fusion puts beyond the slightest doubt, the idea of our primitive mountains having been originally in a state of igneous fusion. This state gives a satisfactory explanation of the form of the earth, of the increase of temperature at greater depths, of hot springs, and many other phenomena. At that time, during this high degree of temperature, the water of the sea must have formed an elastic fluid round the globe, according to the experiments of M. Cagnard de la Tour.

"The primitive mountains are distinguished from the volcanic productions, chiefly in their containing lime and magnesia in the state of carbonates, while they form silicates and bisilicates with the silica in volcanic rocks. It is conceivable, that the silica, which in a higher degree of temperature 'at the ordinary pressure of the atmosphere, drives away the carbonic acid, is on the other hand expelled by the carbonic acid under the influence of a high pressure. It is not, therefore, surprising to find quartz crystals in Carrara marble. But, as at the period of the formation of volcanic rocks, this high pressure, produced by the evaporation of the water of the sea, did not take place any longer, we find in them the same combinations which we obtain in our laboratories, and in metallurgical processes.

"It is proved by many observations, that the level of the sea must have been, at some ancient period, higher than it is at present. This can be easily accounted for, if we consider that water heated must be more expanded than the solid earth. If we suppose with

M. de la Place, that the average depth of the sea is 96,000 feet, and assume the dilatation of the earth to be equal to that of glass, we find, that at a temperature of 100° centigr., the sea would be 4000 feet higher than it is at present, and that it would cover most of the secondary mountains. The melted masses shrink during their cooling. If this happens in large masses, cavities, garnished with crystals, must result, geodes, &c."

Mushet's Process for alloying Copper for Ships.—" In order to increase the tenacity of pure copper, to render it more fibrous, and to prevent the common effects of sea water upon it, Mr. Mushet has taken out a patent for the following process:

"He mixes with the copper, as an alloy, regulus of zinc, in the proportion of two ounces of zinc to 100lbs. weight of copper; or two ounces of block or grain tin; or four ounces of regulus of antimony; or eight ounces of regulus of arsenic, in the same quantity of copper. Or, instead of employing these substances alone in the above-mentioned proportions, to 100lbs. of copper he proposes to add half an ounce of regulus of zinc, half an ounce of grain or block tin, one ounce of regulus of antimony, and two ounces of regulus of arsenic."

Saline Impregnation of Rain.— "After a severe storm on the 5th December, 1822, Mr. Dalton examined the rain that fell at Manchester, and found that it contained one grain of salt, muriate of soda, in 10,000 grains of water; and as sea water contains one grain of salt in 25 of water, there must have been one grain of sea water in every 400 grains of rain water.