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drawn from the petitions, in every one of which it was to be found. It was an allegation of the people of England as to a notorious fact on which they grounded the prayer of their petitions. It was an allegation of the people of England as to a fact which the learned gentleman had moved the committees upon confideration to agree with the people in, as the ground to proceed agreeable to their petitions in the redrets of grievances. That the thus drawing out from the petitions the fenfe of the petitioners, in order to make declaration of that fenfe of the people to the Houle, was fo far from being contrary to the proceedings of parliament, that it was a proceeding conformabic to a cafe in point as that cafe and proceeding ftood in the journals of the Houfe.

fion enfued.] As foon as the tumult ceafed, his lordfhip ring to explain, faid, he was far from acknowledging himself under any obligation to the gentlemen in oppofition; and if it were to their efforts that he owed his permaΑ nency in place, it was because the people at large confidered them as dangerous to their liberties, and dangerous to the conftitution.

Mr. P-tt did not think his meaning could have been fo much mistaken. What he meant to fay was, that, had his lordfhip puriued the line pointed out to him by oppofition, he would no longer have been acceptable at a certain place, but he was aware that the only line that could procure his lordship favour was that which he purfued, and which pe-Coppofition repudiated, and which has fince been found to involve this country in every fpecies of national diftrefs.

See the conclufion of this Debate accurately ftated in our Magazine for March laft.

The Debates in the Seffion for 1780 will be cccafionally continued and concluded in our

MR. URBAN,

N

There never was, he faid, but one riod when there were fo many petitions of this fort prefented to the House as at prefent; that was now just 140 years ago. In the year 1640 there were petitions of this kind prefented in this manner to the Honfe. If inflead, he said, of fuffering ourselves to be told that weD future numbers. are now going on contrary to the proceedings of the Houfe, we look to the precedent of that time, we fhall find that your Magazine for September you have entertained the public with a character of the Houfe on the 10th of November apthe late excellent Mr. Hollis. The leaft fapointed a committee to draw out of the vourable trait of that character, i. e. the afpetitions prefented to the Houfe fome fertion of his never reforting to places of fuch declaration as may be a fair repre-public worthip, I can from the beft autho fentation of the feafe of the petitioners. Now, faid he, what the leained gentle min has done is exactly and minutely conformable to this procedent. And he ventured to alfert, that the committee would hear no more of these objections, of the propofitions being a mere abftract question, and the like; nor of the proceedings of the committee being contrary to the ufual mode of proceedings in par

liament.

In the progrefs of this debate, which was one of the moft interefting during the fellion, Mr. P-t allerted, that it was to the regular, uniform, unremitting fruggle of oppofition to the fatal meaJures that had marked the noble lord's ciniitration, which had kept his lordup fteady in his place.

Ld. N-th replied, if it was true, as 2 hon. gentleman had all rted, that he

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rity (the authority of Mr. Hollis himfelf) affure you is unjuft. Mr. Hollis declared to a gentleman of my acquaintance, that he was in principle a Diffenter; that when in London he conftantly attended divine fervice among the Diffemtors, but when at places of public refort (at one of which they then F were) he generally attended public worthip, one part of the Sunday amongst the Diffenchurch, as an expression of his charity. It ters, and the other part at the established is probable (but I feak this from conjecture only) that Mr. Hollis did not attend public worthip conftantly during his occafional refiGdence at his eftate at Coricombe; as every body knows by what fort of clergymen and in what manner too many of the curacies in country villages are ferved, and that devotion to conducted could not be agrecable to a man of Mr. Hollis's fenfe and goodrefs. An admirer of Mr. HOLLIS.

was kept in office by the efforts of oppo.miftaken the New Norwich H. feandry, which **Our Correfpondent J. B. feems to have n, it certainly was as true that he was kept in place by the efforts of those who dos erly contended against the rights of Great Britain, and who were now purfaing mealuies likely to overturn the conftitution. Here his lordthip was called to order, and confiderable confu

is totally different from the Tullian. The fir mer recommends planting in fingle or double grains; the latter driling. So wub bis already been jaid on the Tullian Handy, that the subject is quite exbayflid.-Tyro and M. S. are beth on fubjects we wish to bave done swith.-Scrutator in January.

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MR. URBAN,

B

Notes refpecting the Plate.-Letter by the late Dr. Bradley. 605 particular way of knowing thereby the pofition of the fpot, in refpect to the ecliptic or equator, which is neceffary in order to find the fituation of the pole of the fpot's motion, and the time of its revolution. Indeed, if he noted the day, hour and minute, of his obfervations, and took care always to keep his board in fuch a pofition with respect to the horizon, that if its under edge was ftrait, it might be always parallel to the horizon, which, by the defcription you gave me, was always the cafe in his method of obferving: I fay, if the obfervations he has already made are thus circumftantiated, he may from

Dec. 14. Y inferting the inclofed figures of fome ancient medals in my poffeffion, for an explanation from fome of your ingenious correfpondents, you will greatly oblige, Yours, &c.

L. L. The Saxon coin, No. 1. is of copper, and about half the size of the drawing. All the reft are copper, and the fize of the drawings, except No. 7, which is filver. No. 4. is a reverfe of the Emperour Conftantine the Great. [See the plate, fig. 1-7.]

MR. URBAN,

Dec. 27.

them determine the pofition of the fut with refpect to the equator or ecliptic. For at the time of obfervation, he must by calculationdetermine the angle made between the ecliptic, and the vertical circle paffing through the

A Mongft the papers of a late eminent Antiquary, I found a plate of a rude infcription, which I am totally at a lofs to decypher. It was engraved for private ufe, at the expence of the late Mr. Rowe Mores; and, if thought worth copying, may contri-O's center; and then, on his board, draw a bute to the amufement of your many learned line through the center, making the fame readers. Yours, &c. EUGENIO. angle with his perpendicular line, and this line will reprefent the ecliptic on the fun's difk.

***We are equally unable with our Corre Spondent to decypher this infcription, or rather (as it appears to us) these fragments of various inferiptions We have contrived, bowever, to have it hitched-in to a Mifcellaneous Plate, and fhall be glad to fee it explained. [See fig. 11.]

MR. URBAN,

TH

HE enclofed, original letter, of the late Rev. Dr. Bradley, Aftronomer Royal, to Mr. Nath, fell into my hands by chance. The fubject is curious; and the eafy method which is pointed out in it, both for making the obfervations and deducing the neceffary confequences from them, may perhaps put fome perfons, who have leifure and a turn that way, on making obfervations of the kind therein mentioned, which are curious, and may have their uses.

Yours, &c. P. Q

SIR, Aug. 24. THE fmall time I was with you yefterday not allowing me fully to explain what I thought would be the moit proper method for your brother to make use of, in order to determine the fituation of the axis of the fun's revolution, and its inclination to the plane of the ecliptic, I thall now beg leave to give you my thoughts on that fubieét.

From what you then told me, I underflood that your brother's way of obferving the fpots was by tranfmitting the image of the fun through a telescope, and receiving the fame, at fome diftance behind the eyeglafs, upon a board, or the like, on which he

had drawn a circle of the fame diameter that he would have the fun's image appear, and to which he made it exactly agree by putting the circle nearer or farther from the telcfcope, as occafion required; and when the image and circle exactly coincided, he noted the point on the board, &c. where a spot fell. But by what you then told me, he had no SUPPL. to GENT. Mag. 1780.

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For inftance; we will fuppofe RRSS the board on which the image is caft, the plane of this I fuppofe he always keeps at right gles to the axis of his telescope, and likewife the fide SS always parallel to the horizon; then VCN drawn through C, the center of the circle perpendicular to SS, will reprefent the vertical circle paffing through the O's center. [See plate, fig. 8.]

If then, for the time of his obfervation, he calculates the angle made between the verti cal and ecliptic (the method for doing of which he will find in Street's aftronomy, in the chapter about calculating the fun's eclipfe) and then makes the angle VCE equal thereto, the line /E will reprefent the ecliptic on the fun's difk; and CP drawn perpendicular to CE, will reprefent the circle of lon gitude paffing through the fun's center, and P the pole of the ecliptic. Suppofe now S was the place of a fpot marked upon his paper or board; then in order to find the real longitude and latitude of the fpot, as feen from the fun's center, it will be neceffary to find the longitude and latitude of that point on the fun's difk reprefented by S. In order to this, we will fuppofe the fun to be at an infinite diftance (for the error, when greateft, that will arife from this fuppofition, will not make an error of above 12′ in the spot's place, and 12 on the fun's furface; when viewed from the earth, fubtends an angle but of 2 or 3 feconds, which is a nicety that our beft obfervations muft not pretend to); I fay, we will foppof the fun at an infinite diftance, and then VENP may be conceived to reprefent the fun's disk projected orthogra phically; in which projection the circles of longitude will be reprefented by ellipfes drawn through the poles P,, and the circles of lati tude by ftrait lines parallel to the ecliptic EC. If therefore through S, the point reprefent

ing

ing the place of the fpot, you draw the line ab parallel to the ecliptic EC; from the nature of the orthographical projection, it is dent, that the arch Fb will be the latitude of the fpot, or making CE radius Ca is the fine of the fpot's latitude; and again, making ab radius, as will be the fine of an angle equal to diff. of longitude between the fpot and fun's center. And therefore that angle, added to or fubtracted from the fun's longitude, according as the spot is to the east or weft of CP, will give the true longitude of the spot, as viewed from the fun's center. But here, instead of taking the fun's longitude, as feen from the earth, you are to take the point oppofite thereto, becaufe for determining the fpot's place, you must fuppofe yourself in the center of the fun. For inftance; if the fun was in the beginning of Aries, then that point of the fun's disk, which to us appears in the center, if viewed from the fun, would be in the beginning of Libra; and fo for the reft.

After this manner he may determine the longitude of a spot at the feveral times of obfervation; from which places, fo determined, the inclination of the fun's equator to the ecliptic, as alfo the point of its interfection therewith, may be found. In order to this, three obfervations of the fame fpot are fufficient, if they are made with fufficient exactnefs, and at pretty good intervals from each other, the farther the better. (Ceteris paribus.)

Let us then now fuprofe, that the longitude and latitude of the fame spot, as viewed from the fun's center, is given in three different fituations (for an example I will fuppofe any thing) the longitudes, for instance, at the three times to be

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10 3 186 19 The latitudes S. 16S 6S. 4 10' Then upon a pafteboard, or the like, I draw a circle as big as I please (as, fig. 9, Ygs) reprefenting the ecliptic, upon the plane of which I would now project the iplere tereographically; fuppofing the eye in the north pole of the ecliptic. Then C, the center of the circle 6, will reprefent the fouth pole thereof; and Arait lines drawn from C will reprefent circles of latitude, and the circles of latitude will be alfo reprefented by circles parallel to the rimitive circle. Then from the nature of the projection the diftance of the circles of latitude from the pole C mult be fet off by taking the tangents of half the diftance of thofe circles from the fouth role. In order therefore to fet down the places of the fpot on the projection for the firit obfervation, I take the arch pac.10°. and draw the line Ca, reprefenting the longitude of the fpot in the firft obfervation, and from the center C towards a 1 fet off Cr equal to the tangent of half the fpot's distance from C, the fouth pole of the ecliptic; that is, equal to the tangent of 36°. 52.

In like manner for the fecond obfervation, I take B33. 18°, and C2 = tang, of 41°. 52; and for the third I make the ang

CD 63.19°, and set off C3= tang, 42°55'Then through the points 1, 2, 3, I draw a circle whofe center I find to be in E. Then a line drawn from through E will give the lonigtude of the pole of the fpot's revolution, which in the prefent cafe would be F, and CH will be the tangent of half the spot's nearest distance, and CG the tang, of hal its fartheft diftance from the fouth pole. Therefore half its leaft diftance in degrees, fubtracted from half its greateft, gives the inclination of the ecliptic to the fun's equator and half its greateft, added to half its leaft, gives the dillance of the fpet from the pole of its revolution. Thus in the prefent cafe I found CT ang. 364. and CG➡tang, 43Therefore the inclination is 70, and the dittance of the fpot 80°. from the pole of its revolution. All this follows from the nature of the ftereographick projection, and upon fuppofition that the fpot is fixed to the fun's furface. For the fun revolving about its axis, the fpot will defcribe a circle parallel to the fun's equator, as I may call it, and all circles on the fphere are projected into circles likewife upon the plane of the ftereographie projection; therefore the place of the spot, when laid down in this projection, will be in the circuinference of a circle, whofe center may be determined from three given points, and not lefs, which is the reafon why I require three places of the fame pot to be ob ferved. From the nature likewife of the ftereographic projection, the center of all the leffer circles are in the fame line of measures, as it is by fame called, with the center of the great circle, to which upon the globe they are parallel; fo that by determining the longitude circle of one, whether a greater or leffer circle, your determine the longitude of all; and confequently the center of the cir cle reprefenting the fun's equator, which in this cafe is the pole of the fpot's revolution.

The longitude of the pole of the fpot's revolution, and its diftance from the pole of the ccliptic, being thus determined, you may then proceed to determine the time of the fun's revolution about its axis. In order to which, you must calculate the angle at the pole of the fpot's revolution, between the firti and lat obfervation, which may be done thus ; toppofe C (fig. 10.) the pole of the ecliptic, and Ethe pole of the fput's motion, CE the circle of longitude paffing through them,C1to the compliment of the fpot's latitude at the obfervaton73-45, and C1 to the distance of the pot from the fouth pole of its equator

So, and the angle 1CE to the difference between the long tude of the foot in the init obfervation, and the longitude of the pole E=4.5°; then CE Leng confidered as a fpherical triangle, it will be as the fine of

E:to the fine of C1, fo is the fine of CE to the fine of the angle CET. In the fame man

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