Transition. New kind of granite. peridot. The same nodules and the same crystals are found in the scoria that compose the craters, whence these lavas issued. The modern currents having almost all flowed through narrow and deep valleys, the torrents have resumed their beds, by hollowing out vast furrows in the lava. Hence result sections admirable for their height, which sometimes reaches to 200 French feet; for the regularity and dimensions of the basaltic columns; or for their extent, as they frequently reach whole leagues. These superb curtains are ornamented with scoriæ at top and bottom. The decompo sition of the lower scoriæ gives rise in certain places to a curious phenomenon. The tuf, or wacke, resulting from it, mixes with the river-mud or sand, which the lava had covered, and these places exhibit a transition of the sort that. Werner admits: that of sand, or clay, to basaltes! The modern basaltic columns of Mezin are unquestionably the finest ever yet observed. The whole system of Mezin rests on a new kind of granite, into which pinit enters in the proportion of a twentieth, a tenth, and even a third. This rock occupies a space of more than 250 square leagues, and extends to what was formerly Forêt, where it serves as a matrix to the substance that was taken for emerald, but is only a translucid pinit. Of this I satisfied myself on the spot. SCIENTIFIC NEWS. Report of the Proceedings of the Mathematical and Physical (Concluded from p. 240.) Respiration of SINCE Mr. von Humboldt's return to France, he has shes. made many experiments on the respiration of fishes, in concert with Mr. Provençal. Spallanzani and Sylvestre had shown, that fishes do not breathe by decomposing water, as some had supposed, but by water obstructing the oxigen dissolved in it, or by coming to the surface to collect oxi gen gen directly from the atmosphere. The experiments of Messrs. von H. and P. have gone farther. Seven tenches were placed under a jar filled with river water, containing 4000 cent. cub. [243-6 cub. inch.]. After living in it eight hours and a half, the analysis of the air still found in the water showed, that the fishes had absorbed in this time 145.4 [8.85 cub. in.] of oxigen, and 57.6 [3-5] of nitrogen, and that 132 [8] of carbonic acid had been produced. ferent gasses on them. In water deprived of air the fishes were uneasy, and in Effects of difabout twenty minutes fell motionless to the bottom. In pure oxigen they appeared to respire eagerly, and spread their gills more. In nitrogen and hidrogen they kept their gills closed, seemed to dread the contact of these gasses, and died soon after they were put into the water containing them. Carbonic acid too kills them in a few minutes. But it is not by their gills alone that fishes absorb oxigen and nitrogen, the whole surface of their bodies has the faculty of acting on these gasses. After the fishes were taken out of the water containing the deleterious gasses, a small portion of carbonic acid was found in it, exhaled probably from their bodies. animals after . Mr. Provençal has also made some experiments on the Respiration of respiration of mammalia after the eighth pair of nerves the 8th pair of had been divided. The animals gradually absorbed less nerves was dioxigen, and produced less carbonic acid, after the operation, vided. At first their respiration was not apparently weakened; but it soon became feeble; and at length ceased altogether: probably from the cessation of the mechanical functions of the thorax. The heat of the animal diminished soon after the division of the nerves, and proportionably with the respiration. fishes. With the functions of the airbladder of fishes we are not Airbladder of yet well acquainted. In some it has a duct communicating with the stomach. In others this duct is wanting, and it contains a peculiar organ of a red colour, and a laminated structure. In some both this organ and the duct are found, and in a few this bladder has muscles. The air contained in this bladder is a mixture of oxigen and nitrogen, the former being in greater quantity in proportion to the depth at which the fish lives in the water. Its absence does not appear Poison of the upas. Juice of dead. appear injurious to respiration, though it does to the production of carbonic acid. Tenches from which it has been removed swim, divé, and rise to the surface, with as much ease as others. Such are the principal results of the different inquiries of Messrs. Duvenoy, Delaroche, vơn Hưmề boldt, Provençal, and Cuvier. Drs. Magendie and Delisle have made many experiments on animals, chiefly dogs, with the poison of the upas. Whether introduced into the system by the blood vessels or lymphatics, by the way of the intestines, or by a wound, the animals died universally convulsed. It appears particularly to affect the spinal marrow, and to enter the system only by means of the circulation. It seems to act but very indirectly on the brain, thus showing an independence between it and the spinal marrow, that is not indicated by anatomy. Mr. Vauquelin has found, that the juice of belladonna, ly nightshade. when swallowed by animals, produced in them a delirium exactly similar to that of opium. Some experiments of Mr. Sage confirm the action of this juice on the nervous system. Gasses inject. ed into the Flood vessels. Stings of insects and fishes. Rotations of crops. Dr. Nysten has examined the effect of different gasses injected into the blood vessels. Atmospheric air, oxigen, nitrous oxide, carbonic acid, carbonic oxide, sulphuretted hidrogen, &e., were not deleterious. Oximuriatic, ammoniacal and nitrous acid gasses appeared to act by irritating very violently the right auricle and pulmonary ventricle. Sulphuretted hidrogen, nitric oxide, and nitrogen were injurious to the contractibility of these parts. Some others so changed the nature of the blood, that respiration was unable to convert it from venous to arterial. In a paper on the means of remedying the sting of the weever, trachinus draco L.; and on the effects of the poison of the tarantula, with the mode of cure used in Spain; Mr. Sage recommends the internal and external use of the volatile alkali. In a report on the Means of improving Agriculture by Rotations of green crops by Mr. Yvart, the committee re commends it as answering the important purpose of showing how land may be rendered constantly productive without exhausting it. Mr. Mr. de Cubière read a paper on the cultivation of the Culture of the bald cypress (le cyprès-chauve), showing the advantages of cypress. this fine tree. Mr. Leblanc, who has resided several years in America, Vicugna. communicated his ideas of the ease with which the vicugna might be domesticated in the Alps and Pyrenees. Mr. Poyfère-de-Ceré read an account of the mode of Wool. washing superfine wool in Spain. Mr. Percy related some curious observations on the fa- Alcarazas. brications of the jars and alcarazas, which the Spaniards employ for preserving liquors, and for cooling them. tone. In the report of the Class of History and ancient Litera- Ancient bell ture, a paper by Mr. Grégoire is mentioned, containing a of very loud description of a singular ancient bell, from the convent of Bobbis, in Piedmont. This bell is about 9 dec. [35.4 inches] in diameter, and of a spherical shape: one hemisphere being complete; the other formed of ten branches, broad at the base where they join the upper half, and ta pering to a point*. Its sound is much louder than that of a bell of the common form of the same weight. A small portion, taken from the ear, was analysed by Mr. Vauquelin, and found to consist of 76 parts copper, 20 tin, and 4 lead. Mr. Vauquelin was satisfied, that these were the only metals present; though, from the smallness of the quantity analysed, the proportions may not be strictly accurate. He supposes, that the lead was an adulteration of the tin, though advantageous to the sound. Messrs. Molard and Montgolfier have cast four other bells of the same form and size, before they had a knowledge of Mr. Vauquelin's analysis, using different compositions. That which came nearest in sound to the original was a mixture of equal parts of copper, brass, and tin. Royal Society of Sciences at Harlem. The prize for the question concerning the insects most Insects in injurious to fruit trees, their natural history, and the means Nothing is said of the thickness of the metal, or of the space left between the points of the branches, which appear from the description not to be united, C. jurious to fruit trees. of 1 Prize ques tions. Graduation houses for making salt. Effects of ma nures. Ancient topo. graphy of Holland. Changes on the coasts of Holland. Ancient and of tides. of destroying them, was awarded to Mr. Fred, W. Freyer, councellor of the court and of the regency of Saxe Hilburgbausen. The following questions, having received no satisfactory answer, are repeated, 1. May graduation houses, for making salt from seawater be established with advantage on the coast of Holland; u d how may they be best conducted, considering the circumstance of the country? 2. From the process lately made in the physiology of plants how far do we know in what way vegetation is promoted by different manures in various soils; and what indications way we deduce from the knowledge we have acquired, with respect to the fertilization of uncultivated and barren land? 3. How far can the study of ancient authors, the examination of antiquities, and observations made on the spot, serve to determine with certainty what the face of this country was formerly, particularly under the dom nion of the Romans, including the course of the rivers, and extent of the lakes, and what changes they have successively undergone? 4. What do historical accounts of acknowledged authenthenticity teach us of the changes, that have taken place on the coasts of Holland, the islands, and the arms of the sea that separate them? and what useful information may be derived from it. 5. Do the tides on our coasts rise higher than in former present height ages, and fall proportionably less low? If so, how far can we determine the quantity of this difference in ages more or less remote, and what are the causes of the changes? Do they arise from gradual alterations in the outlets of the waters, or do they depend on external and more remote causes? Renovation of 6. As the experiments and observations of philosophers the oxigen of have shown of late, that the quantity of oxigen gas emitted the atmus phere. by plants is by no means sufficient to supply to the atmosphere what is consumed by the respiration of animals, combustion, absorption, &c., by what other means is the due proportion between the component parts of the atmosphere continually preserved? |
