« VorigeDoorgaan »
Phosphorescence of Decayed Wood. paration, with the one lately recomThe investigations of M. Dessaignes on
mended by the pharmaceutist Simon of
Berlin. this subject have been recently con
Veratria was discovered in 1819, firmed by experiments made by M. Florio. The results are, first, that
by Pelletier and Caventou, and at the different kinds of decayed wood placed of the genus Veratrum, and particularly
same time by Meissner, in several plants under favourable conditions, exposed to in the root of Veratrum album, or atmospheric air and moisture, are capa- white hellebore, and in the seed of ble of shining in the dark; secondly, Veratrum sabadilla, sabadilla seed. that the emission of light is at a maxi
The sabadilla seed was treated with mum in oxygen, and is destroyed by hydrogen, azote, and carbonic acid;
sulphuric ether, which dissolved a volathirdly, that the wood ceases to be tile crystallizable acid, and a fatty and
other substances; the residuum treated luminous when placed in vacuo, which proves that the phenomenon is only one of with boiling alcohol, a deep brown coslow combustion. It is also ascertained
louring-matter is obtained, which is that a temperature of from 50° to 550 filtered off and evaporated to the conis by no means essential to it, as was
sistency of an extract. Cold water will
now dissolve this extract, except a small believed by M. Dessaignes, at least not when the combustion has com
quantity of fatty matter which is filtered menced; on the contrary, the phospho
off; the solution, however, has to be
concentrated by evaporation, and filtered rescence is not perceptibly diminished by the temperature of ice, and if the of lead, which yields a copious yellow
again, and then precipitated with sugar vessel containing the decayed wood be plunged in a refrigerating mixture of precipitate, and an almost colourless four or five degrees minus, the lu- liquor, which, after having passed some minousness continues for upwards of sulphuretted hydrogen, for removing any an hour, and that heat does not appear rated again, is treated with magnesia.
excess of lead, and filtered and evapoto augment it. M. Florio also ascer- This precipitate, when dissolved in boiltained that if decayed wood, the phos, ing alcohol, which is afterwards to be phorescence of which was maintained by moistening with water, were wetted distilled off again, yields a pulverulent with alcohol, the light was extinguished ish, but which may be whitened' by re
substance, the veratria, which is yellowin a few minutes, while on the other hand, it continued more than a day if peated treatments with alcohol and preoil were applied in the same manner.
cipitations of water. He has also found that this phosphoric holic extract from which alcohol is dis
Couerbe's method is to make an alcolight does not present any trace of tilled off, and this brownish-red extract polarization or of electricity, and, finally, as a simple means of measuring its in- is now boiled with water acidulated with tensity, he arranged three mirrors, and sulphuric acid, until a mineral alkali
does not indicate any precipitate; by found that the light received by the third, after reflections from the first ammonia, the base or veratria is preci
adding now a solution of potassa or and second, was still perceptible in a fourth; and also that the phosphores
pitated in its yet impure state. cence was perceptible through an enve- solved in very diluted sulphuric acid,
For obtaining it still purer, it is dislope of six sheets of thin paper in which and to the sulphate of veratria so obthe wood was enclosed.
tained, are added some drops of nitre, On Veratria.
acid, and the liquor is decomposed by
potassa dissolved, and we obtain the As Veratria now ranks among the most alkaline matter, which is washed with salutary ingredients in Materia Medica, cold water, and redissolved again with it must naturally be of great interest to boiling alcohol, &c. Simon's method, the pharmaceutical and medical world, however, as described in the Berlin to obtain so valuable a substance in its Annals is very simple; the seed is perfect purity, that is, very white, with treated with boiling alcohol, which is out being adulterated with foreign ar- distilled off afterwards, and the extract ticles; the author of these lines take boiled with water acidulated with sulthis opportunity of comparing the phuric acid, until subcarbonate of soda methods hitherto pursued for the pre
will no more produce a precipitate; the
during which period the oil of sabadilla falcon from the Canary Islands, sent to is separated and filtered from it, and the Duke of Lerma, which returned then it is precipitated by subcarbonate from Andalusia to the Island of Teneof soda, so as to leave the fluid alkali; riffe in sixteen hours, which is a passage then put the kettle over the fire, when of seven hundred and fifty miles. The the froth will at once be renioved; story of the falcon of Henry II. is well before it begins to boil, veratria coagu- known, which, pursuing with eagerness lates together, and may easily be re- one of the small species of bustards at moved. It is washed out with water Fontainbleau, was taken the following and discoloured in the following man- day at Malta, and recognised by the ner. After having dissolved it in boil- ring which she bore. Swallows fly at ing alcohol, add then animal charcoal, the rate of a inile in a minute, which and, after agitating for some time, filter would be one thousand four hundred the fluid, which will at last become quite and forty miles in twenty-four hours. clear; evaporate the spirits of wine over That many birds continue their mia sand-bath, and the remaining mass in grations by night as well as by day, and a porcelain dish by means of water- are thus enabled to make an additonal vapours. It is obvious now, in what an
progress, may be easily ascertained from improved manner veratria may be ob
their notes, which, in Autumn and tained by this last process; according Spring, the seasons of their migration, to the first, when the veratria was filtered we often hear by night. The cries of off, and washed out with water, and geese, cranes, and some species of landthen redissolved again, concentrated birds are distinctly heard, and others fly and precipitated again with soda, the silently. Wild pigeons are frequently alkaloid was separated by pressing it seen, at early dawn, in the higher atbetween blotting-paper, and must natu- mosphere. They fly higher by night rally suffer a great loss in the product; than by day, and thus experience less whereas, in the latter, the alkaloid is inconvenience. from darkness. The separated from its acid solution, and it great Hooping Crane scarcely erer runs from itself by means of heat in pauses in his migrations to rest in the the basic fluid to its proper substance. middle States. I have heard his hoarse The product by the former process was notes as he was passing over the highest forty grains from the ounce of clear mountains of the Alleghany; but he seed, and that obtained by the last pro- was always too high to be seen by the cess is fifty-four grains, which is 33 per naked eye. This bird seems to take cent. more. -Silliman's Journal.
wing from his usual winter retreats in
the south, ascends into the higher regions Migration of North American Birds. of the air, and scarcely halts until be By the Rev. J. BACHMAN. arrives at his breeding-places; in or
near the polar regions. From a variety of accurate experiments which have been made at different periods, it appears that the hawk, the wild Singular Employment of the pigeon, (Columba migratoria,) and
Human Race, several species of wild ducks, fly at the rate of a mile in a minute and a half; In Mexico, the fattening of hogs is this is at the rate of forty miles an hour, carried on upon the most extensive scale, four hundred and eighty between the in large establishments devoted to the rising and setting of the sun, and nine purpose. In these, young persons, hundred and sixty miles in twenty-four chosen for their strength of lungs, are hours. This would enable birds to pass employed to sing the animals to sleep; from Charleston, U. S., to the distant and in the intervals of their repose, and northern settlements in a single day, of their meals, these choristers are busy and easily accounts for the circumstance, in appeasing the little jealousies and that geese, ducks, and pigeons have quarrels excited among their charges been taken in the northern and eastern by dyspepsia. It is stated that the states, with undigested rice in their audience show great satisfaction with crops, which must have been picked up the performances, and sometimes throw in the rice-fields of Carolina or Georgia in a few notes, pour encourager lesbut the day before.
Organic Origin of Tripoli Stone. Ecole des Mines or in the Jardin'des
Plantes, nothing is to be distinguished M. EHRENBERG has recently made the but fine equal-sized grains of silica. remarkable discovery that the siliceous The stone from Bilin is of a clear rocks, apparently homogenous, friable grayish-yellow, laminated, presenting and even laminated, and which are all the appearance of a very modern deknown by the name of Tripolies, (polier posit, and entirely composed of organic reschiefer of Werner,) are entirely for- mains; these are cylindrical tubes formed med of distinct remains, or rather ske- by articulated rings, which with numbers letons of infusorial animals of the bac- of detached rings are found simply agcilarian order, and of the genera cocco- gregated together without any cement or nema, synedra, gaillonella, &c. These interposed matter; the rings are of remains, which have perfectly preserved various magnitudes, from the foodoro to the form of the silicified bodies of these the 1058677 of an inch in diameter, their infusoriæ, may be seen with the greatest average altitude being about half their distinctness in a microscope, and may diameter; they may be discerned by be readily compared with the living means of a single lens, magnifying 70 species which have been observed and or 80 times. These fossils are evidently accurately drawn by. M. Ehrenberg: organic remains, but in form they have In many cases there is no appreciable no resemblance to the baccilaria, which difference; the species are discrimi
are prismatic. From what M. Dufrénoy nated by the form, or more distinctly, told him concerning the Santa Fiora triby the number of the transversal septa poli
, which is also a recent deposit, M. which divide their minute bodies; and Dujardin conceives that analogous fosM. Ehrenberg, who has succeeded in sils will be discovered in other siliceous counting them, has found the same friable deposits belonging to the tertiary number of these septa in the fossile and formations; but nothing of the kind is in the living species. His investigations perceivable, even in the pulverulent have been made on the tripolies of siliceous deposit accompanying the Bilin, in Bohemia, of Santa-Fiora, in Menilites of the Paris basin. Tuscany, and on those of Ile-de-France
Chalk taken from certain parts of and Francis bad. It is only necessary the cretaceous formation, has been found to take a sample of one of these tripo- to consist of the débris of minute corals, lies, that of Bilin for instance, to grate foraminifera, and valves of a small a little on a plate of glass, to temper the entomostraceous animal resembling the dust with a drop of water, and then to see
cytherina. It is probable, therefore, by means of a good microscope, thou that organic agency has been more exsands, or rather millions of remains of tensively employed in the formation these animalculæ ; the greater number of the crust of the globe than has of the species are fresh-water, but there hitherto been supposed; the last-menare also marine, especially in the tripoli tioned fact giving additional support to of Ile-de-France. M. Dujardin en- the hypothesis that lime is a product of deavoured to verify this singular dis- organic origin. We hope that the nacovery; his attempts to do so by means turalists of our own country will hasten of the tripolies of commerce, and of to ascertain and confirm the truth of many collections, were totally fruitless; this singular discovery. but fortunately, at the Ecole des Mines, he met with the genuine Bilin tripoli. Hypotheses respecting Aurora M. Dufrénoy pointed out to him the
Borealis. difference between this pseudo-tripoli, which is a fresh-water depôt formed in Our readers are aware that at the late recent geological æras, and tripolies, pro- meeting at Bristol, Mr. Herapath deperly so called, which are either vul- scribed the appearances presented by a canic rocks, or carbonaceous schistus of remarkable Aurora, he witnessed in a very ancient formation, modified by November last, from which he came to igneous agency, as may be served in the conclusion that that phenomenon is that of Poligni, near to Rennes. In these merely electricity passing off from a tripolies, in that of Venice, which is charged cloud, in the act of dissolving yellowish, and whose origin is not in air that can take its water, but not known, as well as in many others, spe- its electrical fluid, which consequently cimens, of which are to be seen in the becomes visible.
Professor Joslin. of Schenectady, U.S. Convenient numerical Expression of the has recently pnblished a paper on the subject of Aurora, and, from a number of
Welfare, fc., of a Nation. observations, comes to the conclusions, M. DUPIN, the present President of the That the temperature of the air is fall- | Académie des Sciences, in his “Reing, and the atmospheric pressure in- searches on the Influence of the Price creasing, on the day in which an Aurora of Corn on the population of France," appears ; that, generally, after an read in May and June last before the Aurora, the atmospheric pressure de- Academy, has come to the conclusion, creases, temperature rises, and water falls that it is untrue to assert that the as snow or rain within two days; that abundance or scarcity of the means of the air at the earth's surface, if not subsistence, acts as the principal and saturated with moisture at the time of predominant cause, in the amount either an Aurora, is much nearer than usual to of births or of deaths in the French that point.
nation, and that "the years in which It will be easily perceived that these the greatest numbers of marriages take results are conformable to Mr. Hera- place, are not those in which the prices path's hypothesis. Professor Joslin, of provisions are the lowest." however, proposes another equally de- He considers it as demonstrated, that serving of attention,--that Aurora is “the fortuitous causes brought into the result of crystallization of the va- action by intemperate seasons, compours of the atmosphere. The follow- mercial fluctuations, and the vicissitudes ing are the principal steps in the argu- of human affairs, produce at the prement.
sent time much greater inequalities in Light is given out during the pro- deaths, marriages, and births, than the cess of congelation, and since it appears extremes of abundance or scarcity. that the state of the atmosphere is “ It is not, then, necessary or useful," favourable to the deposition of moisture, he continues, " for Frenchmen to extol and to its crystallization from the de- the desolating doctrines of Malthus, creasing temperature, it is hence possi- which deprecate the increase of the huble, if not probable, that the light is the man race by the less opulent classes." result of this action. If the molecules of And he rejoices“ that Science is able to crystals have a peculiar kind of polarity demonstrate that the speculative and which governs them in their arrange- systematic theories which freeze up the ment, they may be also affected by the human heart and wound the natural magnetism of the earth, and thus would feelings, are contradicted by facts, and be produced the columns which Aurora have no foundation in experience. usually presents, their fluctuations He then proceeds to take advantage arising from the unsteady nature of the of the newly-discovered and welcome atmosphere and the continual repro- truth in the following manner :duction of light from the crystallization “The minute variations in the annual of new quantities of vapour.
amount of births, marriages, and deaths, It has also been observed, that Au- even when great alterations have taken roras are most common during the place in the price of corn, have led me months of November and December, to seek for a function of these three and that when they consist merely of a social elements, which should exhibit bank of light, like the dawn, the mag- these variations far more sensibly, by netic needle is but slightly affected; but correcting, through the means of each that when beams or streamers are formed, other, the irregularities produced by the the disturbance of the needle seems to numerous unforeseen, accidental, and indicate a more active magnetic energy. transitory causes.
There is no contradiction between “Every general cause of public prothe hypotheses of these two gentlemen, sperity multiplies, on the one hand, the and as all theories are only regarded by births and marriages, and diminishes true followers of inductive science, as the deaths on the other. guides in the collection of new facts by “If we suppose a population so which the real explanation of a pheno- situated as to remain in the same social menon may, in time, be arrived at, and physical circumstances, and which meteorologists will have new incen- should at once be doubled, tripled, tives to extended and accurate obser- quadrupled, &c., the births, marriages vations.
and deaths, would be similarly doubled,
tripled, quadrupled, &c.; consequently, value of the Functions of Vitality is the proportion of the births and mar- 0.5937. riages to the deaths would remain con- “ The second, a period of high prices ; stant, whatever 'might be the increase the mean of the prices is 22 fr. 48c., of the population.
and that of the Functions of Vitality, “I have taken the mean of the two 0.6092. following proportions:
“The third, a period of intermediate, Marriages
or moderate prices ; mean price, 18 fr.
05c.; mean of the Functions of Vitality, Deaths.
0.6168. and I have called it the Function of
“The fourth, a period of the lowest Vitality. “This Function is, as has been seen, of the Functions, 0.6097.
prices; mean price, 15 fr. 69 c., and that independent of the total number of the
“The Function of Vitality of the inhabitants. This, in the existing state fourth, or lowest-price period is, as may of things, offers a great advantage; for be observed, less than that of the third, the fact is, that up to the present day,
or moderate-price period. the census of the whole (French) popula
“It would, therefore, appear to be tion has at all times been imperfect, but most favourable to the welfare of the the Registers of the State have given, nation in general, that the price of corn with great accuracy, the annual number should tluctuate among the intermediate of the births, marriages, and deaths.
prices of 1 fr. above, and of 2 fr. below, “The very evident variations which
18 fr. per hectolitre of wheat. the Function of national Vitality under
“Before a further extension of the goes at the end of a certain number of conclusions which may be drawn from years, are the mathematical expression similar considerations, it will be neand the sure demonstration of the great
cessary to accumulate observations, changes which have affected the welfare and to proceed with great circumof the people. “In the following Table are given temptation to hazard consequences,
spection, so that there may be no the Price of Wheat, and the Function which futurity and facts more carefully under consideration, obtained as above, collected and established, may not confor each year 1817..... 1830. The
firm. years, &c., are arranged into groups,
“ It would be desirable that the value and the fifth and sixth columns con- of this Function should be inserted tain the means of each group.
every year in the Annuaire du Bureau
des Longitudes. It might be placed in Comparative Table of the Prices of the Summary of the Population-Tables
Wheat, and the Functions of Vitality, which have been given-1817 ...1835. for fifteen years, arranged according
“This new element would immeto the Prices, beginning with the diately attract attention to the degree of highest.
welfare or distress enjoyed by the population of France in each of the years
so furnished. Years. Vitality.
“Statesmen, statisticians, and medi
cal men, each in his own peculiar 1817 0.5788
sphere, might then study the causes of 1•18750.5937 30 405 0.6087
the variations indicated by this element, 0-6107
and by this means, much valuable assistance would be afforded to such as may attempt to appreciate the
causes which are favourable or other3.7007/0.6168 18 05 wise to the amelioration of the condition
"Fifty years ago, the mean value of 1.8290 0.6097 15 69
the Function of Vitality, calculated upon an average of fourteen years,
amounted to 0.5403. “The first group embraces a period of “This same Function, calculated on extreme dearness, the mean of the prices an average of fifteen years, from 1817 in which is 30 fr. 40$ C., and the mean to 1831, gives a mean of 0.6103. The
1818 1931 1829 1830 1828 18:20 1819 18:27 1821 1823 1824 1826 1825 1822
2.4368'0.6092 22 49