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in melted tin till it began to congeal.
M. Fontana has conftructed thermometers of great, utility in meafuring the temperature of fluids. Their bulbs are fo fmall as not to exceed one-tenth of an inch in diameter, though the tube may even exceed ten inches in length. On account of the small mafs of these thermometers they almost inftantaneously acquire the temperature of the liquor into which they are immerged, and as quickly lofe it when taken out. The peculiar part of his method of conftructing thefe inftruments consists in taking a tube of a very fine capillary bore, fealing it hermetically at both ends, and grinding away nearly half its thicknefs. This flat furface is to be polished, and ferves to receive the graduations, which are drawn and marked with the fine point of a diamond. The other part of the furface of the tube must be deprived of its polish, in order that the fine capillary cylinder of mercury may be rendered more confpicuous and difcernible. In this cafe, the cavity of the tube being at a very finall diftance from the flat furface produced by grinding, there is little or no parallax occafioned by the thickness and refractive power of the glafs interpofed between the line of divifion and the column of mercury. It is unneceffary to defcribe the method of blowing the bulb, and filling the thermometer, fince thefe are well known to philofophers and artists.
The philofophical world have great reason to hope that the contefted and important question concerning the exiftence of phlogifton will either be decided or very much elucidated by Mr. Kirwan, who is at prefent bufied on that fubject. It is unneceffary for us to obferve that this gentleman, in, addition to the original mental powers and acquifitions he poffeffes, is undoubtedly more intimately acquainted with the prefent ftate of chemistry, and that immenfe mafs of facts, which is fcattered in a great variety of works in all languages, than any other philofopher in England, or perhaps in Europe.
M. Moyroud, in the year 1782, having prefented to the minifter of the finances in France, a memoir, in which he afferts himself to be in poffeffion of a particular procefs, by which, in the fabrication of the natural fteel of Dauphiny, above a fourth part of the confumption of coal, and as great a portion of time, might be faved, without being of the leaft detriment to the quality of the fteel; this procefs appeared to deferve attention. M. Binelly, engineer, and M. Jars, infpec tor-general of the mines, were therefore appointed to affift M. Moyrond in the trials he offered to make before them, which were performed to their fatisfaction, and proved that the advantages to be derived from this procefs were really fuch as M. Moyroud had afferted.
After the reports of Meff. Binelli and Jars were made, a reward was granted to M. Moyroud, on condition of his publishing the procefs, that every manufacturer of steel might reap the advantage of this discovery, by working it in the manner made ufe of in Dauphiny.
In the ordinary manipulation, as foon as they have taken the melted mafs out of the melting pot in the furnace, they hammer it and suffer it to cool before they carry it to the refining furnace.
M. Moyroud's procefs fimply confifts in taking advantage of the heat the mafs of fteel is yet penetrated with, after it has been taken out of the melting pot and undergone the effect of the hammer, to refine it immediately, while hot, and extend it into plates or bars under another hammering. By thus taking the advantage of the heat the mafs had acquired in the first furnace, he faves the coals and the time which neceffarily muft have been taken up to restore the due degree of heat they had ufelefsly loft. But it must be observed, to obtain this advantage, that it is indifpenfably neceffary to have two forges and two anvils in the manufactory.
Mr. Nicholfon has contrived a new inftrument, by means of which the plus
and minus electricities, when ftrong enough to give the fpark, are inftantly diftinguished from each other. This may be of great advantage to philofophers whofe attention is directed to the obfervation of the phenomena of thunder clouds. It is well known how fallacious the form of the luminous appearance at the extremity of a metallic point is, when made ufe of for this purpofe; and the celebrated Beccaria, in his numerous obfervations, was under the neceffity of ufing a long pasteboard tube, in which was included two metallic points, whofe intervals were the difcontinuation of his conductor. The long tube was abfolutely neceffary to enable him to obferve the figure of electric luminous brush with fafety by day-light. Mr. Nicholfon's invention confifis in a metallic ball with which the fpark is to be follicited. By means of a fcrew, a fine fteel point is made to project about one thirtieth part of an inch, or lefs, as may be found most convenient, beyond the polifhed furface of the ball, through a very fmall hole. This point is prefented to the electrized body. If the electricity be plus no fpark will be drawn, but it will pafs to the point in filence, as ufual; but, if the electricity be minus, the uninfulated ball will give denfe and long fparks to the electrifed body.
We are informed that the fame gentleman, fome time ago, explained to a refpectable fociety in London, a new method for experimentally finding the quantity of terrestrial refraction, which is the principal impediment to the ac
curate trigonometrical menfurations of the height of mountains. His method. is trigonometrical, but we do not hear that he has yet communicated to the public any memoir on the subject.
The attention of the philofophical world is much excited by fome experiments lately made by Dr. George Fordyce and Dr. Crawford. With a pair of fcales capable of exhibiting the three thousandth part of a grain, the quantity of about two ounces of water in a glafs veffel, hermetically fealed, was weighed. The water was then frozen, care being taken to make the furface of the glafs perfectly clean. Its weight when frozen was one fixteenth of a grain more than when fluid. The temperature both of the ice and the water was conftantly 32°, and therefore the condenfation of vapour that might be imagined to take place on the glafs muft have been alike in both cafes. Befides which, the experiment has been frequently repeated as well when the temperature of the room was below as when above 32°. And it is to be prefumed that no condenfation could take place when the air itself was colder than the glafs veffel.
From thefe experiments it fhould feem either that the matter of heat is poffeffed of pofitive levity, or that it is only the privation of the matter of cold; or, laftly, if heat and cold be mere modifications, it appears that heat is a modification which not only counteracts and destroys the effects of the cohesive attraction, but even those of gravity.
From the Italian. By a poor MONK.
O, Metaftafio! heavenly bard!
The drama's lord confeft,
Sweet harmony! Italia's boaft!
Thy poet's name revere,
Who calls from Heaven th' angelic host
In vain-when all untouch'd the heart Withholds her pureft praife.
A French compofer.
Thou, Nature, never would'ft prefide
But thou wert present whilst infpir'd
My lov'd Olympiad! oft in thee,
This heart with woe fubdu'd!
The fun when funk beneath the hill,
Leaves me with thee to weep, With thee he finds me weeping ftill,
When he forfakes the deep. What tribute can be paid by me, In humble life conceal'd? Can I an equal praise to thee
(Great Nature's painter!) yield? Thou shedst the nectar of delight That all my foul infpires,
Thy mufe, when the extends her flight, Adds wing to my defires,
Can I to celebrate thy name
This hand untutor'd truft;
And like another Pigal + frame
Here, on the left, by Arbia's fide,
With murm'ring found his flender tide
A graffy hillock rifes fair,
Begirt with filent bowers,
The juniper and laurel here,
By Phoebus ever fam'd,
Titus and Dido's name.
But where th' Olympiad holds a place
And there three garlands bind.
And thrice each day my votive lays
LL hail thou tyrant Love, whose power controuls
The fecret will and paffions of our fouls.
Love is a fecret motion of the mind, To certain objects, where it hopes to find Both reft and fatisfaction. Every breast By love predominant is still poffeft, That o'er our other paffions hath a sway And the beloved object we obey. This Love, we perfect or imperfect find As is the object which attracts our mind. The heart, that's fix'd on objects vile and bafe, Brings on itfelf dishonour and difgrace. And he, whofe heart is fix'd on things fublim'd Thus may acquire an elevated mind.
Love raifes in our minds an ufeful thought Of that beloved object, which hath caught Qur very fouls. This object then employs Our fecret thoughts; our peace it then destroys. In dreams by night it then disturbs our sleep, And from our thoughts by day we can't it keep. A lover's mind is like a ftormy fea That's in perpetual motion; and we fee The foul is feiz'd by love, as is the blood By agues; first a fhiv'ring, then a flood Of burning heat: fo love will always show Of fear and hope, perpetual ebb and flow.
In Love, the hero's courage we may view, The man's fears, the madman's folly too; And at first fight, we equally may fee
'Tis raging madness, then neceffity.
It is now joy, then grief-now hopes, then fears,
Hope is the lover's refuge, and he'll find,
An Italian compofer.
A French fculptor.
The winged infects, and the reptile tribe,
It braves the world, and rules both fmall and great.
It fmooths the edge of all our fmarting woe.
On Ida's lofty hill, by Paris feen,
When on her form the fhepherd fix'd his eyes,
Thro' all the maze of life, where'er you bend
For Death will come, and that fine form will fade,
Stella foar on (to nobler objects true)
The dubious Atheist well might doubt a heaven:
THE MISLETOE AND THE PASSIONFLOWER.
A FABLE. By Mr. LANGHORN.
In this dim cave, of different creed,
The holy hermit's paffion-flower.
Penfive I laid, in thought profound,
I hear it ftill-Doft thou not hear?
Unlike to living founds it came,
Unmix'd, unmelodiz'd with breath;
Who was not nurs'd at Nature's breast. Affociate he with dæmons dire,
O'er human victims held the knife, And pleas'd to fee the babe expire,
Smil'd grimly o'er its quivering life. Behold his crimson-streaming hand Erect!-his dark, fix'd, murderous eye!" In the dim cave I faw him ftand;
And my heart died-I felt it die.
1 fee him ftill-Dott thou not fee
Dart thro' the fable fhade of hair?
What meagre form behind him moves,
Untrue to nature, virtue, fenfe.
Tho' Nature lent him powers tɔ aid
The moral caufe, the mutual weal: Those powers he funk in this dim shade, The defperate fuicide of zeal. Go, teach the drone of faintly haunts, Whofe cell's the fepulchre of time; Tho' many a hely hymn he chaunts,
His life is one continued crime.
And bear from hence the plant, the flower;
They have the duties of their hour--
In what receffes of the brain?
What corner of the mind?
Within th' attentive mind:
Without the aid which we receive rrom thee How fhort-liv'd would the pleafures be Which moft our fancy fire!
Like bubbles floating on the filver stream, As tranfient as a midnight dream,
As fuddenly expire.
Thy faithful records long imprefs'd retain The fenfe of pleafure, and of pain, LOND. MAG. April 1785.
When pain or pleasure's o'er :
When ev'ry prefent object fails to please,
When pleasure did abound:
Thus we can trace the beauties of the spring, And to our minds its fragrance bring,
When winter reigns around.
By thee alone all knowledge we attain;
In vain fair science spreads her ample store,
It will avail us nought.
E'en Tully's eloquence in vain would charm, Or Plato's heavenly wisdom warm,
If traces none remain
Of what we read, or what attentive hear: The mind a defert must appear
Where Mem'ry does not reign.
O, Pow'r Supreme! from whom alone mankind Derive this faculty of mind,
Vouchfafe to hear my prayer:
All bad impreffions from my breast remove,
Be ever treafur'd there.
Teddington, Feb. 17, 1785.
Written the 30th of March, 1784.
O! Winter still obfcures the chearful day, And with his ruffian blafts affrights the fpring!
No fprightly notes are warbled from the spray;
Nature again a wintry garment wears,
No leaves, no flow'rs, no bloffoms we descry:
And all her vernal charms once more to find. So when the clouds of black misfortune rife, And unforeseen diftress the breast affails, Should we look forward to ferener skies, And cherish hope of more propitious gales. CLASSICUS.
Teddington, March 12, 1785.