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An aurora on the 11th, in the even- , made at Brest, that when the weight of ing, displayed, during four hours, lu- the atmosphere elevates the mercurial minous arches, and a vast field of light. column of a barometer ģ in., the mean Again, on the next day, there was a level of the sea, (taken as in the pregradually decreasing column; rain; ceding article,) is depressed about fourand then came on those south-west teen times as much, or 1 inches. The gales which were so severe and fatal on proportion of the specific gravity of the coasts.

mercury to sea-water being as 13:3 to 1, The last observed aurora was visible M. Daussy concludes that the mean on the 18th, and attracted universal | level of the sea may be considered a notice in the metropolis, from the great true barometer, its changes always extent of its deep-red colour*. Rain corresponding with those of the atmofollowed, but the barometric column, in spheric pressure. this case, did not sink; on the contrary, This remarkable result having been it steadily rose, and its ascent exceeded disputed by Mr. Lubbock, -as, in the the mean height.

observations made on the tides at A comparatively dry period succeeded; London under his supervision, no indithe atmospheric pressure remained high cation of this connexion was detected, until the 27th: it then fell with the north- M. Daussy felt obliged to ascertain, by westerly wind which preceded and experiments made at other points, if the brought in the late cold weather and fact observed at Brest was merely local, deep snow.

depending upon the immense basin, so

nearly shut in, which spreads itself Advantage of Chlorine in the Conver- before the entrance of that port. He sion of Iron.

took advantage, for this purpose, of It has recently been discovered at an some tidal observations, which were iron-work in Germany, that by producing ordered to be made by the Government a disengagementof chlorine in the finery- in 1835, on different parts of the French furnaces used for converting iron into coast, and principally of those at L'Orient, the second and third qualities, an article where the localities were favourable to may be obtained equal to that of quality the convenient observation of high and No. 1. This new process has been car.

low water. He compared these with ried into effect in the furnaces on the the barometric observations made at Lower Rhine, and is said to have com.

the same place during the months of pletely succeeded.

August, September, October, Novem

her, and December, 1835. The result Mean Level of the Sea.

of this comparison confirmed his previous The level of the sea, to which the opinion, of the correspondence between barometric measurements of altitude the greatest heights of the mean level are referred, as to a standard level, is of the sea and the lowest of those of obtained, in the practice of the most the barometer, except that the motion eminent French hydrographers, by

of the mean level is a little more marked

at L'Orient than at Brest. taking the mean between the average height of two consecutive flood-tides

M. Daussy was. further convinced and that of their intermediate ebb; or,

that this effect was not owing, as some reciprocally, the mean between the persons are disposed to believe, to the

“ To determine average height of two consecutive ebb- intluence of the wind. tides and the height of their interme- this," he says, “I observed, successively, diate flood.

during each kind of wind, regarding

both its force and direction, and exaThe Tide, a true Barometer.

mined if the heights given by the mean

level did not, in each series, follow an In a memoir on the Tides of the order analogous to that of the barometer; Coasts of France M. Daussy states, I was soon convinced, that the same that he has been induced to believe, law of variation did take place, and in all from a great number of observations winds,—that is to say, that the wind re

* About 8 P.M., police, firemen, and maining constant in direction and force, boys, were running in all directions, expect it was always found that the height of ing to find a fire in the next street, or at the mean level varied with the effect of farthest, in the next street but one. The atmospheric pressure." The number bustle and perplexity lasted about an hour. ) of these observations was small, and

the conclusions drawn from them can tons. The reputed elegance of its apply to the port of L'Orient only: they form, the style of its bas-reliefs, and are the following. First, That light the richness of its metal, composed of winds have little influence on the height gold, silver, and copper, contributed to of the mean level, whatever may be their make it remarkable as a specimen of direction. Second, That fresh breezes the advanced state of the art of casting have still less influence. Third, and in Russia, at the epoch of its execution. lastly, That gales and strong winds M. Montferrand, a gentleman greatly from the N. and N.E. depress the mean distinguished in Petersburgh by the level about 34 inches, and that similar numerous works he has executed, was winds from the S. W., S., and S.E., intrusted with the direction of the elevate it to the same amount.

operations. As the bell was lying in a Since the publication of these latter cavity in the ground, and more than observations of M. Daussy, Mr. Luh- thirty feet below the surface, a large bock has been induced to examine excavation was made to clear it. Over further into this interesting cause of this was constructed a strong and lofty variation in the mean level of the sea, scaffold* for the attachment of the blocks, and which had, previous to M. Daussy, and for the temporary suspension of the escaped attention. He has announced, bell at a proper height. At half-past that Mr. Dession, having, at his re- five in the morning of the 5th of July quest, calculated the heights and last, the authorities of Moscow and a times of the tides at Liverpool for the large number of spectators being asyear 1784, and compared the results sembled on the spot, prayers were obtained by him with the barometric offered up for the success of the attempt, heights of the same year made by Mr. and the operations commenced on a Hutchinson, this conclusion is arrived signal given by M. Montferrand. Six at, namely, that for 1 in. depression hundred soldiers instantaneously set-to of the mercurial column, there is a at a large number of capstans. The corresponding elevation of the mean

enormous weight was mastered, and the level of the sea, amounting to one inch. bell was soon seen to rise slowly in the With regard to the epochs of the tides, pit. Forty-two minutes elapsed during no sensible connexion with the atmo- its elevation to the necessary height. spheric pressure was observed. This No accident occurred. The first operais a remarkable and satisfactory cor- tion being finished, the next was to roboration of the fact observed by M. build a platform beneath the suspended Daussy. It may now be desirable to bell. This was completed in eight adopt the term, Standard Level of the hours, and the bell lowered upon it. Sea, (or some similar one,) when ele- On the following day it was placed on vations are referred to the sea-level,- a sledge, and drawn, by means of an meaning by the new term, the mean inclined plane, up to the pedestal inlevel of the sea at a certain constant tended to support it, and there finally height of the barometer.

left, on the 26th of the same month.

This colossal work of art is, after all, Lifting of the Kremlin Bell.

but a mere curiosity. Its use as a In the month of July, in the present bell is impossible, from a fracture, about year, a successful attempt was made to seven feet high and two feet wide, in raise the enormous bell which had been the lower part, where, as has been so long buried in the earth, in the stated, it is 23 in. thick. The cause of Kremlin, at Moscow. This bell, one of this gigantic injury rests entirely upon the wonders of Moscow, was cast, in conjecture. 1733, at the command of the Empress Anne, by a Russian founder, Michael Thermometer indicating Mean Motorine. It is, according to Clarke,

Temperature. 21 ft. 41 in. high; at two feet from the A METHOD of accurately ascertaining bottom its circumference measures 67 the mean temperature of the atmoft. 4 in.; its diameter at that height is sphere at any given time and place has consequently about 21 ft. 6 in. Its

a desideratum, not only thickness, at the part intended to be

long been struck by the hammer, 23 in. The among meteorologists, but among phy. Russians estimate the weight at 12,000 * Said to have been fifty feet from bottom poods, which is nearly 200 English to top.

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siciens in general ; for, independent of To apply this principle to the purpose other important considerations, it is in- of marking mean temperatures, M. Jurtimately connected with the determina- gensen first rererses the arrangement tion of the law that regulates the distri- of the metals in the curveri bar, so that, bution of heat over different climates; instead of compensating for any variaand it is only by obtaining the mean tion of temperature, it magnifies the temperature of a place at different and effect of it; he then increases this sendistant periods, that the great question sibility to variation by adding a second can ever be solved, as to whether the arc, and by these means he obtains a temperature of this country, or of the variation of 314 seconds for each degree globe in general, is increasing, station of temperature. It may now, after a ary, or diminishing.

little reflection, be conceived, that if Ordinary thermometers, it is well this instrument be compared, at two known, give the temperature of the distant instants, with a chronometer atmosphere at the moment of observa- keeping regular time, we could ascertion only; there are others contrived to tain, by changing the differences of indicate the maximum and minimum lime into degrees, the mean actual temperatures which may have occurred temperature of the period. It would be between any two selected epochs,—but necessary, of course, previously to adjust no instrument has yet been constructed this instrument to the thermometer, so which would accurately ascertain, and that the march of the two instruments register, the mean temperature of the may be uniform and comparable. In periods between two such epochs, how- order to render these chrono-thermoever short it might be.

meters still more useful, M. Jurgensen A skilful timepiece-maker of Copen- adds, without much increasing their hagen, M. Jules Jurgensen, eminent bulk, a metallic thermometer, which for the excellence of his chronometers, indicates present temperature, and this, and for a Treatise on Detached Escape- by the aid of two slides upon it, is made ments, has succeeded in an attempt to to give also the maximum and miniproduce such an instrument. It is, in mum temperatures which may have fact, by means of chronometers that he occurred between any two instants of exhibits the mean temperature desired* observation.

It is generally known that, to prevent This ingenious instrument, therefore, variations of temperature affecting the gives, on inspection going of a watch, there is attached to 1. The temperature of the present the balance-wheel of good instruments moment. a curved bar, composed of two metals, 2. The maximum temperature of the the unequal dilatation and contraction period between the present moment and of whichi, under the same temperature, that of any other moment previous to shortens and extends the curve, and it which we have selected. thus accelerates or retards the motion. 3. The minimum temperature, and, In the Edinburgh Encyclopædia, Art.

4. The mean temperature of the Atmospherical Clock, a machine is stated to same period. have been proposed by Dr. Brewster, which

The principal objection that presents should record any variation of temperature itself to this desirable instrument is the that takes place during a given period, and cost, which necessarily occurs in all indicate on the dial-plate the exact average cases where chronometers are required. of all the heights of the mercury in the thermometer. The principle is, " that the

Indelible Writing Ink. variations of heat and cold affect the pen- DURING a recent discussion in the dulum, which may be either of the tubular | Académie des Sciences on the merits of or gridiron kind, and which is so constructed as to render sensible, in the motion fraudulent removal of characters written

some paper prepared to prevent the of the clock, the alternate contractions and dilatations which it undergoes.”

upon it, M. Dulong called to the recollecmerous inquiries as to the actual existence tion of the Academy, that a commission of this instrument, we have never been able appointed by them had demonstrated, to give a satisfactory answer.

A full de- that the surest means of rendering scription was promised to be given in a sub- written characters indelible, was to use sequent part of the Encyclopædia,—but Indian ink dissolved in water, with a eitlier this was not done, or it has eluded slight mixture of some acid, more parmore than one attempt to find it.

ticularly tho hydrochloric.

To nu

a

Parisian Mechanics' Institution.

geometry in this country we exposed

and remarked upon recently*; and, An Association for the instruction of unwilling to be merely querulous comartificers, &c. has been in activity in plainers, we, at the same time, comParis for about four years, and latterly menced an attempt to render, as far as with remarkable success.

may lie in our power, this delightful The first idea of it is said to have and extensively useful branch of science originated with the late celebrated geo- better known amongst us. metrician, Monge. The members are, It would be a waste of time to dwell principally, students of the Ecole Poly: upon the vast importance of an intitechnique, and their benerolent and mate acquaintance with the means of enlightened object is the rational in- preserving health, and of avoiding disstruction of the working classes. The ease, to individuals and to society. following enumeration of the subjects No limit can be assigned to its benetaught will show the value and the scope ficial consequences, -and yet how deploof the labours of the Association. rably deficient are all our great establish

1. The elements of arithmetic, geo-ments of individual and professional metry, and drawing of the human education, with respect to this valuable figure and ornament.

species of knowledge! The care of the 2. Descriptive geometry, its appli- public health is absolutely abandoned", cation to masonry and carpentry; me- until perhaps the nose or the pocket chanics, drawing of machines, physics, of some influential individual is affected. and chemistry.

If he raises the question of a nuisance, 3. Grammar, book-keeping, Hygiène how lamentable then is the hostile (the art of preserving health).

array of scientific ignorance. On quesThe whole course embraces a com- tions much less complicated and obscure plete system of mental instruction than the effects of miasma, vapours, adapted to the classes for whom it is &c. upon the human body, there is not intended,

the slightest difficulty, in any case, of The members of the institution have obtaining any number and weight of had the satisfaction of seeing the num- opinions on one side, and balancing ber of workmen who avail themselves these by an equal weight and number of its advantages increasing every yea on the other! and so unsettled is the During the winter of 1834-5 the courses general mind on these subjects, that of geometry and of grammar had never this shock of evidence, so morally less than 200 auditors; 625 artificers lamentable, reflects no disgrace upon were on the lists for the class of draw

any party. ing. As spring advances and employ- On a threatened visit of a dangerous ment increases, a sensible diminution epidemic, what absurdities are promulin the numbers is evident,—but the gated and adopted as infallible preamount of the students, even in summer, is from 900 to 1000; in the winter it is

Page 305 of the present volume, from 1400 to 1500; they are nearly all of 'muriatic acid gas, precipitated weekly

+ Think of several millions of gallons adults. The expense of the lectures, and uninterruptedly from the summit of a &c. has been hitherto defrayed by the lofty chimney, upon a crowded population members of the Association, and by of a large town! This is now, and has been grants from the Government and the actually for years, the case at Newcastle; municipal authorities of Paris.

happily for the survivors of the imme

diate neighbourhood, if there are any, it is Two capital Omissions in all the British not intended to continue much longer. A Systems of Public Instruction. process, recently patented by Mr. Maugham,

the Chemical Lecturer at the AdelaideTHERE are two subjects of public in street Gallery, is about to be adopted at struction mentioned in the preceding

the manufactory in question. By this proarticle, which, though evidently of the is made to enter into a new combination,

cess the gas, immediately on its evolution, highest importance, are never

taught and, instead of rushing up the chimney to in Great Britain ;-we refer to Descrip- vitiate a large field of atmosphere, and tive Geometry, and Hygiène, or the pre- annoy the vicinity, it will never enter the servation of health, and the prevention, chimney at all, but be instantaneously not cure, of disease.

fixed in a saleable product, viz., chlorate The astonishing neglect of descriptive of lime used in bleaching,

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rentives or cures! No intelligent guide celebrated English botanist, Ray. It or competent adviser is at hand, and the is with pleasure that we insert the folpestilence may rage, not only without lowing passage from the prospectus of check, but with aggravated mischief, in this association :-“Ladies are eligible consequence of the general ignorance. as members, it being well known that It is well when masses, as well as in there are many who have devoted their dividuals, profit by adversity and mis- attention with success to this delightful fortune. The effects of the cholera at study, and whose occupations often Paris were severely felt, and though the leave them much leisure for observation attacks of that dreadful visiter no pre- and research." caution known can evade, yet it is gratifying to see the authorities of Paris, Number of British Species of Plants. roused by the terrors which it produced, sparing no cost, no labour, to remove The number of species of plants found causes supposed to be favourable to its in Great Britain is about 1500. This extension. The general attention is comprises all those which exist in Lapnow sensibly alive in that metropolis to land and Sweden, with scarcely any

It includes about threethe advantages of cleanliness, drainage, exception. and ventilation, and we have little doubt fourths of those which grow in Gerthat this excellent idea of teaching the many, and about two-fifths of those of principles of Hygiène to the workmen France; the southern and sea-board who attend this institution suggested provinces of the latter country adding itself at the same epoch.

greatly to the variety of its vegetable It is fortunate that, though discoveries productions. in this important science may require the

The vicinity of London may be conunited assistance of several others, and sidered extremely rich in objects of the subtlest investigation of their most botanical research; for of the 1500 intelligent cultivators, yet its practice species of plants belonging to Great may often be reduced to measures of Britain, about 1000 may be found within mere precaution, and generally to opera- 25 miles of the metropolis. Mr. Irvine tions of great ease and simplicity. A has observed 670 of them within two more popular or interesting subject

miles of Hampstead, and 900 within could scarcely be suggested to the many there are great inducements to the

the same distance from Croydon. Thus able lecturers who su frequently address the numerous auditories of every class inhabitant of this smoky city to issue during a London winter. And let us

from its loaded atmosphere, and pursue ask, why should not a science which the delightful and healthy researches of would so essentially and largely con

the botanist.--IRVINE, Meeting of the tribute to the happiness of all mankind, Botanical Society of London, Nov. 1836. be taught from a Chair in every university and public school ? What immense Bored Well at Grenelle. fields are there for its exercise in our The well now boring in the slaughtercrowded manufactories, our mines, our house (abattoir) of Grenelle, near prisons, our ships, our over-peopled Paris, had in September last been districts, indeed, in every single dwell- carried down to a depth of 1150 feet. ing, and in the habits and daily life of When about 1000 feet deep, the temevery individual !

perature at the bottom of the bore was.

720 Fahr.; at the surface of the ground The Botanical Society of London,

it was 51° only. The friends of botanical science, which we recently mentioned as likely to Geological Co-operation. embody themselves into a society, have finally done so, under the title of The the Elbe, in Saxony, more recent than

“ Is the granite on the right bank of BOTANICAL SOCIETY LONDON.

the chalk ?" has long been a fertile They meet at their rooms, ll, John

source of dispute among German geoloStreet, Adelphi, every alternate Thurs- gists. Dr. Cotta, who had examined day, at 8, P.m. The anniversary of the the country with MM. Humboldt and society is fixed for the 29th of No- Rose, has written largely upon it, but vember, that being the birth-day of the argues that, to arrive at any degree of * See p. 321.

certainty upon the subject, explorations

OF

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