242 MISCELLANIES. English Industry in Scientific Research. "Or the fifty-five simple substances recognised in physics, twenty-two, and of the forty-five metals, seventeen, have been discovered in England." Our countrymen may plume themselves, if they please, on this fact. We sincerely wish that they could lay claim to an equal proportion of the whole of the great physical laws, and of the formula by which those laws are expressed, the results of profound analytic investigations based on carefully-repeated experiments, and requiring more intensity of mental exertion than the discovery of a new body, which is most commonly fortuitous. New Method of cultivating the Cerealia. he, "I saw the fact with my own eyes. also, and remarked at the time what a Dr. Jeng, an Austrian physician, saw it very extraordinary circumstance it was. I therefore give it as perfectly correct." Our readers may remember that the late Sir J. Banks and Sir C. Blagden, remained in an oven with a shoulder of mutton till this was thoroughly baked. not abrupt changes of temperature, The power of enduring great, though has been put in a striking point of view during the late Polar expeditions. In the winter of 1833-4, Captain Back and his party, while residing at Fort Reliance, on the Great Slave Lake, were exposed to an average temperature of 33° (65° below the freezing point,) during the whole month of January, and on the 17th, the thermometer was as low as-70°, (102°— inches of mercury, exposed in a common saucer, became solid in two hours. MM. EDWARDS and Collin, in a joint fr. pt.) A six ounce bottle of sulphuric memoir on agricultural chemistry, have ether was laid on the snow; in fifteen shown, that by sowing our principal minutes the interior upper part of the species of cerealia in the summer sea- phial was coated with ice, and the ether son, a profitable harvest of straw, or became viscid and opaque; a similar fodder, may be obtained the first year, bottle of nitric ether indicated the same the plants not flowering, owing to the effects in two hours. Pyroligneous acid elevation of temperature; and that the froze in thirty minutes at a temperature following season, the same plants, expe-of-57° (89°-fr. pt.); a surface of four riencing the usual gradations of teinperature, will furnish an abundant harvest of grain. This proceeding has been successfully adopted with rye, by a member of an agricultural society at Valenciennes; he last year sowed the rye, and towards the close obtained two cuttings of green fodder; this year the same plants flourished so well, that they had attained a height of seven feet a month before the usual time of harvest. Great variation of Temperature borne by the Human Body. Ar the Hot-Baths of Kukurli, at Broussa, in Bithynia, (the natural temperature of which is as high as 183°... 189° Fahr.,) the Duke of Ragusa states (in the notice of his Travels in the East, lately communicated to the Académie des Sciences by M. Arago,) that he saw a Turk remain for a long time in a water-bath, whose temperature was 165° Fahr. This fact, which appears incredible, the Duke affirms in the most positive manner; "for," says "On the 4th of February, the temperature was-60° (92°-fr. pt.), and there being at the same time a fresh breeze, large logs on the fire, in a small room, I was nearly insupportable: with eight could not get the thermometer higher than+ 12° (20°-fr. pt.,) and ink and paint froze on a table placed as near the fire as I could bear the heat"- "the skin of the hands cracked and opened into unsightly gashes, which we were obliged to anoint with grease. On one occasion, after washing my face within three feet of the fire, my hair was absolutely clotted with ice before I had time to dry it." On the 25th of January, the thermometer was at -18° (50°-fr. pt.,) and on the 26th it had risen to + 22°, (10° — fr. pt.,) while on the following day, it fell again to - 49° (81°-fr. pt.,) thus, in the course of twenty-four hours, an inequality of temperature of 71° had been experienced; on the 8th of February, a difference of 38° took place in the 1 same time, and on the 21st, of 43°. On the 3rd of April the thermometer was at + 51°, (19° + fr. pt.,) and on the 28th of May, it stood at + 81° (49° + fr. pt.,) and yet on the 1st of that month it had been down at 11° (43° - fr. pt.) When the party set out on their expedition in the month of June, they travelled over the ice on the lakes and rivers, and yet were compelled to journey by night, because the oppressive sultry heat during the day was so great, as to fatigue the men, and knock up the dogs; and yet the thermometer frequently fell below the freezing-point, during the night. New Link between the Great Divisions of Organized Beings. M. GUERIN has detected under each of the first rings of the abdomen, in the Machilus polypoda, of the order Thysanoura, orders of respiration analogous to those found under the abdomen of many of the Crustacea; in all other respects the insect perfectly agrees with the characters of its class. works of MM. Biot, Gay-Lussac, Pouillet, &c.; he then adds, "but notwithstanding these authorities, such a view of the subject is incorrect, in fact, the temperature of the vapour which rises from a saline solution in ebullition, is independent of the nature and of the quantity of the salt dissolved; it is, under the same barometric prèssure, absolutely the same as that of the vapour which rises from pure water." M. Rudberg had been led to make some rigid inquiries into the subject, after having found that water put into ebullition, either in vessels of glass or of metal, always gives out, under the same atmospheric pressure, vapour of precisely the same temperature, although the water itself, when it boils, be, as M. Gay-Lussac had already observed, actually hotter when it is in the first kind of this case the difference of the temperatures of boiling water is produced by an unequal adhesion of the water to the interior surfaces of the vessels, it would appear more than probable that, in the same manner, the attraction of the salt vessels than when in the second. As in Vapours of Saline Solutions and of by the water raises the solution only to Water, same in Temperature. Ir is generally admitted, that the aqueous vapour which is disengaged from saline solutions in ebullition, has exactly the same temperature as the superior stratum of the solution, and that thus the vapour possesses, but in this case only, an elasticity equivalent to the atmospheric pressure, a less, consequently, than it would have attained at its maximum of density, when its temperature would be much higher than 212°. It appears also natural, that each rising bubble of vapour should acquire immediately the temperature of the fluid which surrounds it on every side, and should continue at the same time to be subject to a certain expansion until its elasticity becomes equal to the atmospheric pressure. This also perfectly agrees with what happens, when vapour is disengaged from saline solutions at a low temperature, by the effect of evaporation; the vapours of such solutions being always less elastic than that of pure water, at the same temperature. "All physiciens appear to hold on the temperature of vapour, the opinions we have just expressed," says M. Rudberg, and he quotes to support this assertion, several passages from the a temperature superior to 212°, without exercising any analogous influence on that of the vapour. The experiments of M. Rudberg have fully confirmed this conjecture. He began by constructing an apparatus which could not be affected by the influence of any external disturbing circumstances; he then made his experiments on different days, and under different atmospheric pressures. His intention being principally to ascertain by these means, if the temperature would follow a corresponding march to that of the barometer, because, in this case, it would be the best proof that the cause, through which the vapour possesses a temperature inferior to that of the saline solution, and exactly the same as that of the vapour of distilled water under the same pressure, ought not to have been sought in the refrigerating action of the air, but in the phenomenon itself of the formation of vapour. During these series of experiments, M. Rudberg examined many times the temperature of the vapour of distilled water, principally with the intention of ascertaining if, by the effect of continued heat, the point of ebullition of the thermometer did not undergo a small change of place. This point was raised, in fact, 0.054 Fahr., and subsequently remained at this height. The liquids which were submitted to experiment were solutions of muriate of lime, of neutralized carbonate of potash, of saltpetre, of common salt, and of sulphate of zinc. At the commencement of each series of experiments, the solutions were so concentrated that there remained, at the temperature of the chamber, much salt undissolved: by boiling the solutions again from time to time, they were gradually still more concentrated. The conclusion drawn from the experiments was, that the vapour which rises from a saline solution in ebullition has precisely the same temperature as that which is disengaged from distilled water under the same atmospheric pressure, whatever be the number of degrees which the temperature of the solution may be still more elevated by reason of the quantity and the nature of the salt dissolved. Such is the first consequence, to which the results of these experiments have led M. Rudberg, in the most satisfactory manner. Other important ones seem also to flow from them, but these have not yet been established beyond doubt by direct experiment. If we now consider the formation of vapours in saline solutions by evaporation, the experiments of MM. Dalton, Gay-Lussac, and Prinsep, have established that the vapour of a saline solution has an elasticity much less than that of pure water, when the two liquids have the same temperature. It therefore follows, inversely, that for the same elasticity, the vapour of a saline solution is hotter than that of pure water. It results likewise from experiment, that this difference of temperature increases with the quantity of salt dissolved, and that it also varies according to the nature of the salt. From these two results it clearly follows that between the temperature of vapour and its elasticity, the relation is sensibly different, according as the vapour is produced by the ebullition of a saline solution or by evaporation from its surface. The cause of this difference, and that of the uniformity of the temperature of vapour formed by water and by saline solutions, under the same atmospheric pressure, can only be finally ascertained by a more exact examination of the formation of vapours in saline solutions by evaporation. New Term in Physics. It is now well ascertained that certain Comparison of distant simultaneous HRR. GAUSS, Astronomical Professor Phosphorescence of Decayed Wood. THE investigations of M. Dessaignes on this subject have been recently confirmed by experiments made by M. Florio. The results are, first, that different kinds of decayed wood placed under favourable conditions, exposed to atmospheric air and moisture, are capable of shining in the dark; secondly, that the emission of light is at a maxi mum in oxygen, and is destroyed by hydrogen, azote, and carbonic acid; thirdly, that the wood ceases to be luminous when placed in vacuo, which proves that the phenomenon is only one of slow combustion. It is also ascertained that a temperature of from 50° to 55° is by no means essential to it, as was believed by M. Dessaignes, at least not when the combustion has commenced; on the contrary, the phosphorescence is not perceptibly diminished by the temperature of ice, and if the vessel containing the decayed wood be plunged in a refrigerating mixture of four or five degrees minus, the luminousness continues for upwards of an hour, and that heat does not appear to augment it. M. Florio also ascertained that if decayed wood, the phosphorescence of which was maintained by moistening with water, were wetted with alcohol, the light was extinguished in a few minutes, while on the other hand, it continued more than a day if oil were applied in the same manner. He has also found that this phosphoric light does not present any trace of polarization or of electricity, and, finally, as a simple means of measuring its intensity, he arranged three mirrors, and found that the light received by the third, after reflections from the first and second, was still perceptible in a fourth; and also that the phosphorescence was perceptible through an envelope of six sheets of thin paper in which the wood was enclosed. On Veratria. As Veratria now ranks among the most salutary ingredients in Materia Medica, it must naturally be of great interest to the pharmaceutical and medical world, to obtain so valuable a substance in its perfect purity, that is, very white, without being adulterated with foreign articles; the author of these lines take this opportunity of comparing the methods hitherto pursued for the pre paration, with the one lately recommended by the pharmaceutist Simon of Berlin. Veratria was discovered in 1819, by Pelletier and Caventou, and at the of the genus Veratrum, and particularly same time by Meissner, in several plants in the root of Veratrum album, or white hellebore, and in the seed of Veratrum sabadilla, sabadilla seed. The sabadilla seed was treated with sulphuric ether, which dissolved a volatile crystallizable acid, and a fatty and other substances; the residuum treated with boiling alcohol, a deep brown cofiltered off and evaporated to the conlouring-matter is obtained, which is sistency of an extract. Cold water will now dissolve this extract, except a small quantity of fatty matter which is filtered off; the solution, however, has to be concentrated by evaporation, and filtered of lead, which yields a copious yellow again, and then precipitated with sugar precipitate, and an almost colourless liquor, which, after having passed some sulphuretted hydrogen, for removing any excess of lead, and filtered and evaporated again, is treated with magnesia. This precipitate, when dissolved in boiling alcohol, which is afterwards to be distilled off again, yields a pulverulent substance, the veratria, which is yellowish, but which may be whitened by repeated treatments with alcohol and precipitations of water. Couerbe's method is to make an alco holic extract from which alcohol is distilled off, and this brownish-red extract is now boiled with water acidulated with sulphuric acid, until a mineral alkali does not indicate any precipitate; by adding now a solution of potassa or ammonia, the base or veratria is precipitated in its yet impure state. solved in very diluted sulphuric acid, For obtaining it still purer, it is disand to the sulphate of veratria so obtained, are added some drops of nitre, acid, and the liquor is decomposed by potassa dissolved, and we obtain the alkaline matter, which is washed with cold water, and redissolved again with boiling alcohol, &c. Simon's method, however, as described in the Berlin Annals is very simple; the seed is treated with boiling alcohol, which is distilled off afterwards, and the extract boiled with water acidulated with sulphuric acid, until subcarbonate of soda will no more produce a precipitate; the ner. whole liquor is set aside for settling, during which period the oil of sabadilla is separated and filtered from it, and then it is precipitated by subcarbonate of soda, so as to leave the fluid alkali; then put the kettle over the fire, when the froth will at once be removed; before it begins to boil, veratria coagulates together, and may easily be removed. It is washed out with water and discoloured in the following manAfter having dissolved it in boiling alcohol, add then animal charcoal, and, after agitating for some time, filter the fluid, which will at last become quite clear; evaporate the spirits of wine over a sand-bath, and the remaining mass in a porcelain dish by means of watervapours. It is obvious now, in what an improved manner veratria may be obtained by this last process; according to the first, when the veratria was filtered off, and washed out with water, and then redissolved again, concentrated and precipitated again with soda, the alkaloid was separated by pressing it between blotting-paper, and must naturally suffer a great loss in the product; whereas, in the latter, the alkaloid is separated from its acid solution, and it runs from itself by means of heat in the basic fluid to its proper substance. The product by the former process was forty grains from the ounce of clear seed, and that obtained by the last process is fifty-four grains, which is 33 per cent. more.- -Silliman's Journal. Migration of North American Birds. By the Rev. J. BACHMAN. FROM a variety of accurate experiments which have been made at different periods, it appears that the hawk, the wild pigeon, (Columba migratoria,) and several species of wild ducks, fly at the rate of a mile in a minute and a half; this is at the rate of forty miles an hour, four hundred and eighty between the rising and setting of the sun, and nine hundred and sixty miles in twenty-four hours. This would enable birds to pass from Charleston, U. S., to the distant northern settlements in a single day, and easily accounts for the circumstance, that geese, ducks, and pigeons have been taken in the northern and eastern states, with undigested rice in their crops, which must have been picked up in the rice-fields of Carolina or Georgia but the day before. There is a well-attested account of a falcon from the Canary Islands, sent to the Duke of Lerma, which returned from Andalusia to the Island of Teneriffe in sixteen hours, which is a passage of seven hundred and fifty miles. The story of the falcon of Henry II. is well known, which, pursuing with eagerness one of the small species of bustards at Fontainbleau, was taken the following day at Malta, and recognised by the ring which she bore. Swallows fly at the rate of a mile in a minute, which would be one thousand four hundred and forty miles in twenty-four hours. That many birds continue their migrations by night as well as by day, and are thus enabled to make an additonal progress, may be easily ascertained from their notes, which, in Autumn and Spring, the seasons of their migration, we often hear by night. The cries of geese, cranes, and some species of landbirds are distinctly heard, and others fly silently. Wild pigeons are frequently seen, at early dawn, in the higher atmosphere. They fly higher by night than by day, and thus experience less inconvenience from darkness. The great Hooping Crane scarcely ever pauses in his migrations to rest in the middle States. I have heard his hoarse notes as he was passing over the highest mountains of the Alleghany; but he was always too high to be seen by the naked eye. This bird seems to take wing from his usual winter retreats in the south, ascends into the higher regions of the air, and scarcely halts until he arrives at his breeding-places, in or near the polar regions. Singular Employment of the Human Race, IN Mexico, the fattening of hogs is carried on upon the most extensive scale, in large establishments devoted to the purpose. In these, young persons, chosen for their strength of lungs, are employed to sing the animals to sleep; and in the intervals of their repose, and of their meals, these choristers are busy in appeasing the little jealousies and quarrels excited among their charges by dyspepsia. It is stated that the audience show great satisfaction with the performances, and sometimes throw in a few notes, pour encourager les autres. |