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made the loan himself while he was in Mr. Martyn spoke handsomely of office.

Lord John Cavendish; but on saying Mr. Pitt replied, that his time was that Lord North had ruined the nation, wholly taken

up

between negociations and ought to be called to an account, abroad and at home: that the state of Mr. Fox said he did not fuppose any the nation was unsettled whether for one would second the honourable mempeace or war; and his own seat at the ber in calling his noble colleague to Treasury so very precarious that it account. He did not think that any would have been the height of impru- one entertained even the idea of it! dence in him to have undertaken a mat The question was at last put, and ter of such a nature as the loan. carried without a division.

45';

ASTRONOMY. AN ACCOUNT OF A REMARKABLE PHENOMENON WHICH

ATTENDS THE FIXED STAR ALGOL, IN THE HEAD OF MEDUSA. DISCOVERED BY MR. GOODRICKE, SON OF SIR JOHN GOODRICKE, OF

BRAMHAM-PARK, NEAR YORK. IT T was first, I believe, discovered by 24 20" so' each. Again February 6th,

Montanari, an Italian, that the mag at 8", after two periods of 21 205 521 nitude of Algol was variable. Ma- each. Again the 23d, at 12" 15", afraldi observed the same thing about ter fix periods of 220' 42' each. the years 1692 and 1693, as may be Again the 26th, at 9" 30', after a finseen in the memoirs of the Royal Aca- gle period of 24 21 15' Again March demy of Sciences at Paris, for the year 21st, at 8" 30', after eight periods of 1695; The latter took notice that it 24 204 52'{, each. Again April 1oth, varied from the second to the fourth at 10h 15', after seven periods of magnitude; but neither of these gen. 2d 20° 49' Again the 13th, at 8", aftlemen discovered that this variation ter a single revolution of 20 21" had any fixed period. Mr. Goodricke, but Mr. Goodricke thinks this a bad led by what had been said by Maraldi, observation. Lastly, on the 3d of May, began to observe Algol sometime in at 9" 15', he observed the same thing the latter end of the last year; and on again, after seven periods of 2d 20° 45' the 12th of November, at 8" 30' in each. The medium of these ten gives the evening, for the first time, saw it 24 201 55', 8, for the length of one at its greatest obscuration. It was 3"{ period; or if we reject the two single from the time that he first perceived it periods, which are both of them longer to diminish to the time of its greatest than any of the others, where the erobscuration, and as much in recovering rors of the observations are divided its usual splendor. He observed its into a greater number of parts, the greateit obícuration again Dec. 28th, time of one period will be 2' 20" 47'5. at 5" 30', after an interval of 454 21"; Mr. Goodricke remarks that Algol, which, if we suppose it to contain 16 when at its greatest brightness, is much periods, gives 2° 20° 49' for the time less bright than a Persei, not so bright of one period. January 14th, 1783, as y Andromeda, brighter than a Cahe observed the greatest obfcuration, a fiopea or B Arietis, and nearly the third time, at 9" 15'; which, fup- fame, if not rather brighter than a Peposing this interval of 17° 3" 45' to gali, and B Casiopea. At its leaft contain fix periods, gires 2+ 20% 37.'1 magnitude, it is nearly of the fame for the time of one period. He ob- brightness as e Persei. The relative served it again on the 31st, at 14" 15', magnitudes of these stars, according to after an interval of six periods, of different observers, are as follow:

Stars

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2.3

2

2

[blocks in formation]
[blocks in formation]

Stars Names. ¡Ptolemy. Prince Tycho. Hevelius. Flamsted. La Caille. Bradley.

Hesse. 3 Persei (Algol)

3
2.3

3
Perfei
y Andromeda 3 3
a Cafiopea

3

3
3

3

3
B Arietis
3 3 3

3
3
3

3
a Pegasi
B Casiopea

3

3
3

3

3 p Persei 4 4 4

4

4 This variation of the light as well of Algol are, I shall here collect toas the periodical time of its returning gether all that has come to my knowhas also been verified by Mr. Edward ledge on this head; that such as have Pigot, to whom Mr. Goodricke had opportunities of observing them may communicated his discovery The examine further into this matter. same things have also been verified by The first thing we meet with on reMr. Herschel, to whom the discovery cord of this kind, was observed by had been communicated by the Rev. Hypparchus, about 170 or 180 years Dr. Makelyne, Astronomer Royal. before Christ; at which time a new star Mr. Herschel relates, that he saw Algol appeared; but of what degree of brightat its greatest obfcuratior. May the 3d, ness, or in what part of the Heavens, I 1783, from 8' 53'to 109 10'at Wind. do not find. We may, however, supfor: the medium is gh 30'; or 15' pose it to have been of a considerable later than it was determined by Mr. magnitude, or it would not have been Goodricke, at York. York is about taken notice of in those times, when

of a degree to the west of Windsor. aftronomy was fo little cultivated, and . Mr. Herschel saw the same phænome- so little was known of the number, non again on the 20th of May, from magnitudes, and situations of the fixed 14" 171 to 14", 30'; the medium is stars. The next new star we meet with 14" 24. The interval between Mr. on record, is that mentioned by LeoHerschel's two observations contains vicius to have been seen in the confix periods of 2" 20" 49 'each; agreeing stellation of Casiopea, about the year with those determined by Mr. Good

945.

He tells us, also, of another ricke, as near as can posibly be ex very bright one, seen near the fame pected. Mr. Herschel sent an account constellation, in the year 1 264. Many of his first observation to the Royal astronomers think these two were the Society, which was read there before fame star, and the fame with that fathe account given by the first disco- mous one in the chair of Casiopea, verer, Mr. Goodricke; but this account which, as far as can be gathered from of Mr. Herschel's observations is taken the belt accounts of it, blazed forth, at from a letter which Mr. Herschel wrote once, with the brightness of Jupiter; to M. De la Lande, and which was printed and which was, at one time, equal in by him in the Journal des Sçarans, for fplendor to the planet Venus. WolJuly lait. The account of Mr. Good- fanges Schuleras was, perhaps, the first ricke's observations is made out from astronomér who saw this astonishing memorandumis taken at the reading of phænomenon, on the 6th of November his paper, and therefore may be liable 1572, abant 6 o'clock in the morning, to fome numerical errors; but, I farter at Wittenberg, and thought it to be a myself, to no material ones.

It was seen by P. Hainzelius, As the magnitudes of many of the at Austerg, on the oth; and by Coro fixed stars have been observed to be nelius Geinma, at Lorain, on the oth. variable, and as it is highly probable that Tycho raw it not before the uth in the variations of several may be sub the evening, immediatelv after fun-fet, jected to itated periods of time, as those at Copenhagen, not far from the ze

LOND. Mac. Sept. 1733.

comet.

nith; and relates that he was so fur- De Nova Stella anni 1572, in which he prised with the fight, that he could has determined its place in the ecliptic, 1carcely believe his own eyes. Hiero- from very accurate observations, to nymus Munofius, then professor of Ma- be 8. 6 54, and its latitude 530 thematics at Valentia, in Spain, says 45'N. He moreover informs us, that he is certain this star was not visible on in all positions of its diurnal motion, the 2d; because that night he pointed he found its distance from other fixed out the stars of Casiopea's chair to his stars invariable; from which he juftly pupils, without perceiving any such inferred, that it was free from parallax, thing:

and consequently placed far beyond any This star formed a rhombus with the of the planets, in the region of the ftars, a, b, and y of Casiopea, and re- fixed stars. mained constantly in the same position Kepler, and several other astronoduring the whole time of its being vi mers observed another star of this fort fible, which was about 16 months. in Serpentarius, from the month of . During the month of November it O&tober 1604, to the end of the year was fo bright as to be frequently seen 1605; which, it is said, equalled Juafter the sun was up; but in the month piter in luftre. In 1600 Kepler also of December it began to decline a little discovered a new star in the breast of in its luftre: it however still continued the Swan, which Bayer has marked as bright as the planet Jupiter. In Ja- P, and which remained visible until the nuary 15,73, it was sentibly less than year 1660 when it disappeared; but in Jupiter but stilll more conspicuous the year 1666 it was again seen by Hevethan the stars of the first magnitude, lius in the very fame place. Before even than Sirius, to which it seemed its disappearance, Hevelius remarks that equal in the months of February and it was of the 3d magnitude; but when March. In the next two months it it was seen by liim the second time, he did not exceed the stars of the ad mag could not estimate it more than the nitude; and in the months of June, fixth; under which circumstances it reJuly, and August, it appeared of the mains at present. Besides this, there lize of the larger stars in Cafiopca's are two other itars in this constellation, chair, which were then accounted of the namely, one in the head, observed by 3d magnitude. In September, O&tober, Hevelius, in 1670, and that marked X and November, it was thought to be by Bayer in the neck; in which some of the 4th magnitude; and in Decem variations hare been observed, I ber it was thought to be rather less than may add that the learned Montanari, the star near it, marked by Bayer. professor of Mathematics at Bononia, In January 1574, it was still of about in a letter to the Royal Society dated the 5th magnitude; was but juft dif- April 30th, 1670, says that two itars cernible in February; and in the month bʻand, Navis, both of the second of March was totally extinct. Its light magnitude, were then wanting, notfor many days after its firft appearance, withitanding he himself had observed was white and sparkling: afterwards them in the year 1664, on account of it inclined somewhat to a yellowish the comet which then appeared in that caft; and in the spring of 1773 it was part of the Heavens. of a darkith red, like that of the planet In none of these, mentioned above, Mars, or the itar Aldebaran. In May has any thing been discovered that in it became of a pale white, much like the leaft denctes a periodical return. that of Saturn, and retained that co The only circumstance of this nature lour until a few days before it totally that has come to my knowledge, bedisappeared, when it changed into a fore the discovery of Mr. Goodricke, kind of muddy white.

is in the star marked o, by Bayer in the Abore twenty aitronomers employed neck of the Whale; and on that actheir pens on this folijed, and particu- count called the Miraculous Star. The larly Tycho Brahe, who has left us an variability of this star was first remarked excellent work on the subject, entitled by David Tabricious, a German astro

nomer,

nomer, in the year 1595. For eight or tude; Tycho, Bayer, Hevelius, and nine months of the year this itar is Flamsted of the third: yet to Montawholly lost to us; and for the other nari it appeared but of the fifth. Dr. three or four months it is constantly Bevis makes it scarcely of the fourth: changing its lustre and bigness. Some La Caille makes it of the fourth; and astronomers have pretended to say, that Dr. Bradley a double star of the third. its periodical returns are regularly made Bayer represents & Andromeda of the in about 339 or 340 days; but others fourth magnitude: Cassini, in the latassert that the periodical returns are ter end of the last century, found it extremely irregular. Its greatest mag- confiderably less. Both editions of the nitude is also different, at different British Catalogue give it of the fourth returns; being sometimes equal to stars or fifth; and Dr. Bevis says it scarcely of the second magnitude, while at exceeded the fifth magnitude in 1740. others it is scarcely equal to those of We meet not with this star in the Cathe third.

talogues of La Caille and Bradley. Besides these there are several stars M. Cassini lost the star No. 49, of which may be suspected of variations Andromeda, in Flamited, and marked -of this kind. Ptolemy makes a Dra- ž, but wrongly, in the 2d edit. for conis of the ...rd or fourth magnitude. some time before the year 1695. In Ulugh Beigh, in 1437, makes it a finall that year it became again visible, and one of the third. The Prince of Hesse, between the years 1740 and 1750 was in 1593, makes it of the third. Tycho of the fifth magnitude. in 1600, and Bayer, soon after, put it The ist edit. of the British Catalogue of the second, and the latter marked makes a Gemino (Castor) between the it with the letter a, as the most emi- first and second magnitude: the 2d nent in the constellation. Hevelius in edit. makes it of the first. Dr. Bevis 1660° makes it of the third; and so says, that between the years 1740 and does Mr. Flamsted, in 1690; but Dr, 1750 it was sensibly less than 3, which Halley in his edition of the British Ca- all agree in making of the second magtalogue, in 1712, puts it down only nitude. Ptolemy makes both of the of the third, though he has been heard second; Tycho Brahe, the Prince of to say he remembered it a very good Hesse, Hevelius, La Caille, and the fecond. Between the years 1740 and present Astronomer Royal the fame; 1750, Dr. Bevis says it was between but Dr. Bradley makes both of the first the third and fourth magnitudes; cer- magnitude. tainly less bright than ., and not It seems highly probable that sevebrighter than 4, in the same constella- ral of the fmaller variations, here mention: yet La Caille makes it of the tioned, may be entirely owing to difthird magnitude in 1755, or. 1756, and ference of judgement in the observers; Dr. Bradley of the second magnitude but there are others so great that they in 1760.

cannot poilibly be placed to that acAgain. Ptolemy and Ulugh Beigh count. make o Serpentis of the fourth magni

P. Q.

M E C H A N I CS. A SHORT ACCOUNT OF THE MACHINE LATELY ERECTED,

BY COMMAND OF HIS MAJESTY, AT WINDSOR, FOR RAISING WATER OUT OF A VERY DEEP WELL TO SUPPLY THE CASTLE,

HIS machine is said to be the in- that could escape no person's observawish we could record his name) who ships; but which, like many other took the hint from observing the great things that pass daily before our eyes, quantity of water which every rope had never been applied to any useful brought on board with it that had been purpose. The application is as simple drawn through the water: a circumstance as the principle.

CC 2

A

A groved wheel, about three feet placed to receive it, by the pressure of diameter, is fixed on an axis, which the rope upon the wheel, in passing tums horizontally over the well, and over it. And so great is the fimplicity an endless rope, of a sufficient length and effect of this machine, that we have to reach into the water in the well, been told by a very excellent mecha, passes over it in the grove. On the nic, who has seen it, that notwithstandjame axis a winch is fixed at one end ing the well is near 200 feet deep, he to turn it by; and, at the other end, turned the machine with one hand, so another wheel, loaded with lead, which as to raise water fufficient to fill a pipe, acts as a fly, to increase the velocity. the diameter of the aperture of which Cn turning the wheel, each part of appeared to him, equal to the diamethe rope, as it comes to the bottom, ter of the rope that raised it. This, passes through the water; and, on ac at least, is certain; the well had been count of the above-mentioned proper- long disused before this machine was ty', the water adheres to, and is brought erected over it, on account of the difup by it to the top, where it is dif- ficulty they found in raising the water charged from the rope into a cifern, out of it,

MATHEMATICS.
MATHEMATICAL QUESTIONS.

16. Question I. by MATHEMATICUS, of Greenwich. It is required to determine the dimensions of the greatest oblique cone, which, when ftanding on its base, fhall but just support itself from falling; the distance of the vertex from the middle of the base being 9 feet,

17. Question II. by Mr. John Dale, of Knightsbridge In the summer of 1783, the sun was observed to rise N. 65° 41' E. and the same day its meridional altitude was 61° oo': what was the latitude of the place, and the day when this observation was made?

The other question proposed by this gentleman is answered in Robert, fon's Navigation.

18. QUESTION III. by the late Mr. GEORGE Brown, of Portsmouth. Given the sum of two numbers, 2, and the sum of their gth powers, 32, to determine the numbers by quadratic equations.

If This question has been proposed before; and the reasons for re-proposing it will appear in the answer.

19. QUESTION IV. by J. P. Given the vertical angle of a triangle, the line bisecting it, and the sum of the sides about it, to construct the triangle.

20. QUESTION V. by Ben SUIB NOR Ben. Through three given points, to describe a square, the area of which shall be equal to å given rectangle; and to determine the limits of poflibility when no two of the points are in the same side of the square.

21. QUESTION VI. by NAUTICUS. Three ships sail from three ports which all lie in the parallel of 47° 8' North, and meet in latitude 44° 24'N. The distance between the two extreme ports is 200 miles; and when they met, the Mip which failed from the middle port had run 216 miles: it also appeared that the rhumb the failed on bifected the angle comprehended between the rhumbs on which the other two ships had failed. Required the distance run by these two Mips, and the courses of all three.

IT The answers to these questions must be sent, polt paid, to Mr. Baldwin's, in Paternoster-row, London, before the ift of December, 1783.

MEDICINE,

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