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finger along the middle angle, I intercepted the blue rays; and by pasting a strip of paper on this plane of my prisin,
made two spectra. But to place the
#. the possibility of doubt, I.
red by means of another prism at the light passing through, and perceived those finges, as if hanging from the angles. Indeed, it is surprising, that these cir. so easily proved, so evident to the eye, and so highly important in heir gonsequences, should have escaped observāśion of such able and accurate - *::::... already menti
... shall conclude this paper with gllowing deductions. That incident light has never yet decomposed; and that Sir, Isaac wton and others only decomposed reflected from opaque substances, or fringes of blue, red, and yellow. '3. That there are but three primary Colours, blue, red, and yellow, by the #ture of which, in different states of -oidéâsation, all the others are formed. 3. That Herschel, Leslie, Davy, Enild, and other philosophers, drew
their conclusions, relative to the heating
power of the prismatic colours, from errooneous data, viz. from experiments on reflected light, whose heat must in a great measure depend on the reflecting media, aid also on the thickness or thinness of the parts of the prism, through which the fringes pass; thus the red and yellow passing through the very thin angle, must be accompanied by more radiant caloric than the blue rays which pass through the thickest. But as I am at present engaged in a series of experiments to prove that the prismatic coloured rays have similar heating powers, I shall not here anticipate. The following diagram will demonstrate my opinions.
To the Editor of the Monthly Magazine. SI R, . ANY reasons prove the vast distance of the fired stars. But in endeavouring to ascertain what that distance is, these circumstances ought not to be omitted. The Sun at 30 min, contains 1800 seconds.
At the Herschelian planet the angle is therefore about 1' 40", the distance being near 20 of ours; at 100 times it would be 20", and at 2000 times 1".-2000"— 120,000" Were the Sun therefore removed to 120,000 times his present distance from us in winter,” he would still subtend an angle of 1". At twice that distance of 30", half a third. - At 3 times this distance, or 360,000 times his present distance, he would subtend an angle of only 20". There is no doubt that an objectshining
like our Sun, by inherent light, might be vi
sible as a vivid point at this vast distance. Most therefore of the fired stars which are visible to the naked eye may be, and most probably are, thus distant. And by a telescope stars may be discernible 100, 1000, even 10,000 times this distance, though by loss of light, they will not be seen so distinctly as if we were brought as much nearer to such stars as the power encreases the angle. But 100,000,000x360,000x10,000– 360°,000,000,000,000,000=364 g = 360 billions of miles. It seems possible therefore that with our present means of observation we may see, and that Dr. Herschel and some few other astronomers have seen thus far of the Universal System : so that it is probable telescope stars are seen, the light of which has been 750 years in reaching ust. And if a diameter of any of the fired stars of the 1st or 2d magnitude, for beyond it cannot be expected, could be measured with accuracy, we might judge what their distance must be by this scale; and at least discover what either that or their magnitude must be to subtend such an angle. And it may be doubted whether such. stars as Sirius, Capella, and Spica, and Regulus, Antares and Arcturus, Aquila and Lyra, are more than 240 or 250,000 times farther from us than our Sun. But then on the other hand, it will be
FTAccurately, his present diam, is then (Jan. 1,) 32' 34"16: as it is (June 1) 31', 34" 12. -
# It seems that Dr. Herschel has observed objects vastly of more remote origin.
TOS probable that almost all telescope stars are much more than 4 or even 500,000 times more remote. And indeed that stars of the 6th magnitude cannot be less than 360,000 times our distance. And stars of the 7, just discernible to the naked eye, not less than 600,000 times: so that the telescope stars nearest to us are probably 860,000 times as distant as the Šun from us; or 86°,000,000,000,000 ==8612, or 86 billions of miles. This will not appear enormous if it be considered that at 400,000 times our distance stars even of the first magnitude have been generally considered to be; which would make them 39 billions of miles distant: or nearly half of the distance here conjecturcd for & the nearest of the telescopic. -
Mr. Pond's late observations as astronomer royal, by shewing that of the parallactic angle, even of Aquila, if any, is nearly insenible, give an additional proof of the amazing distance of the fixed stars.
If Parker's burning lens has ever been applied to bring the rays of Sirius, when near the meridian, to a focus, and no sensible heat has been produced, this, I think, would prove that Sirius cannot be nearer' than 300,000 times our distance. The No. solareosgooooo being 90000000000. Wow, a mirror, or a lens, which should have a power of concentration as 30,000 would reduce this to G53556 of the Sun's force here; which I apprehend might be
sensible to a very delicate thermometer
with a Nonius.
If a parallar in the fired stars be ascertainable, perhaps it will be found in Si**, Aldabaran, or Spica; if a sensible Siameter, perhaps in Arcturus, or Foma. out. If a parallar of 6" had existed in Sirius, which would reduce his diameter to about # of a second, and its distance ** Tows of the G), surely so considerable * Paraslar would ere now have been ascertained, and a disc so sensible could hardly have been altogether overlooked. -o- CAPE1. Lofft. To the Editor of the Monthly Magazine, IGNOR, a hamlet near the village of Bury, has lately become reowned as having produced some of the finest relics of art extant in this coun. oy, in a tessellated or Mosaic pavement. The circumstances attending its discovery are as follow; Mr. Tupper, the P"Prietor, a farmer, was, as usual, Ploughing his fields after the harvest 9f 1811, when, in this field, which he himself has ploughed for the last thirty or forty years, the ploughshare received
Mosaic Pavement lately discovered.
a violent shock from a large stone. On examination it was found to be connect
ed with others, so as to form the remains.
of a wall, and on pursuing their researches, a fine pavement was discovered of various hues, and on which are depicted, first a majestic eagle with Ganymede, most exquisitely defined, with an eye that challenges superiority on canvas; also, a fine portrait of a female,
a place in the pages of your widely-difused miscellany, the particulars herein - eful to other similar soin existence, or hereafter to
be established. . . . o society which I am now speaking of goes its origin to the private exertions ofew individuals, who, about the year agreed in contribute the small sum per month, each, towards the purase of books for their mutual use and
*pience... This plan meeting with ation, and several other persons rous of joining the original it a meeting held Jan. 1, 1786, a ićries of articles were drawn up, and signed by the persons present, for the establishment of an association, to be
called the “Lewes Library Society,” the object of which was to collect, as far
as their finances would allow, the best
works-ex ht in the various departments
o to increase the portunities of knowledge to each menaso ber, and the public in general.
From this small beginning, now 28 years since, the society has gradually increased to its present condition, being composed of 82 members, and possessing 4% a library of about 2450 vols. viz. folios fly 30, quartos 220, octavos 1280 (besides * 350 of the principal magazines, reviews, * &c.), and duodecimos 570, of which a t catalogue is printed for the use of the members. It is regulated by the series o
of articles before-mentioned, occasionally, altered as was found necessary for the convenience and welfare of the society. That the reader may understand the leading principles upon which the society is constituted, I shall give an abstract of the chief of these articles as they mow stand: e 1.2. A meeting to be held quarterly, for transacting the business of the society, at which five members shall be competent to act." - - 3. § person obtaining by ballot the approbation of two-thirds of the members at a meeting; and paying five guineas, to be admitted a member, and entitled to a share in the library. - ;4. The members may dispose of their **Mao. No. 352, o e*.
more than three days.
respective shares, and the purchaser producing a certificate, and obtaining the approbation, &c. (as before) to be admitted a member. 5. A member to be elected to act as president and treasurer, 6. Every member to pay annually one pound to the fund of the society. 8. At every meeting any member may propose a work for the library, eithet in person or by writing; and those which the majority of the members present approve, to be purchased. . . 9. No work of greater price than three guineas to be balloted for, unless proposed at a previous meeting. 12. The books and other articles bea longing to the society, to be the joint and equal property of all the members. 13. Members residing in the neighbourhood may take one volume at a time from the library, and those at a distance, two volumes, which they may respectively keep thirty days, but no volunie to be takest away until the same shall have been one month in the library. A Magazine, or Review, may be taken with any other volume or volumes, having been seven days in the library, but which no member is to keep 14, 15, 16, 17. Penalties for taking a book before, or keeping it after the time allowed; injuring or losing the same ; procuring more than the limited number; neglecting to enter in the library book any volume taken; wilfully making a false entry; lending a book out of the society, or neglecting to pay subscription. Upon the foregoing abstract I shali only remark, that though the price of admission has been advanced from time to time, according to circumstances, yet even at present it is less to each member than one-third of the original cost of the books, and it has been kept so low, in order to induce persons to join the society till the number of members should amount to one hundred; and also, that the article allowing the sale of shares, upon death, removal, or otherwise, always keeps up the number of members, which is material to the success of the . plan for establishing a permanent sibrary. Dec. 20, 1813. LEWESIENSIS. -orTo the Editor of the Monthly Magazine. SI R, * , ERMIT me, through the medium of your excellent publication, to request for myself, aud the rest of your astronomical readers, some information respecting the following modern astre nomical catalogues. 1. The celebrated Lalande, with his nephew and niece, within the space of Q about
1 10 about ten or eleven years, ascertained the positions of between 40,000 and 50,000 stars, from 0° to about 116° of N. Pol. dist. the catalogue of which was published in separate portions in the Connoisance des Temps, for the year 7, (1799) and subsequent volumes, nearly up to the present time. 2. Cit. Vidal, at Mirepoix, ascertained with great care and accuracy, the positions of 838 austral stars, for January 31, 1798. (I suppose this catalogue is intended as a supplement to that of Lalande.) 3. M. Piozzi, astronomer at Palermo, in Sicily, published about 1800, or 1801, a general Catalogue of Stars; but whether a compilation, or an original work, I know not. Quaere the contents, arrangement, and peculiarities of these three Catalogues, of which the above short account is all I have been able to find. If any of your correspondents should he in possession of, or have access to all, or any of the above Catalogues, an account of them, inserted in some future number of your Magazine, will be interesting. Perhaps some of your correspondents may likewise be able to point out in what modern Catalogue the following stars of Bayer's are to be found. They form only a part of the characters omitted by Flamsteed, in his great work, which is far from containing ail the stars observed by preceding astronomers. × Andromeda (52*)—é, p, a And. (the latter of these is not in Fl. and I suspect the other two are not the same as in Bayer,)—J. Aurigae—a Cassiopeiae—w or b Cassi: (one of these two is not in FI.)— e Cygni (26*)—a Eridani, (see Phil. Trans. lxxvi, 204, 295.)—g Geminorum (62 :)-x, J. Gem. (6, 15, Cancrif)— *] Herculis, b Persei, (see Miss Herschel's Cat. No. 3 and 4.)–9, 1, x, Sagittarii, y, Ś, o, ø, ok, Scorpii, (20, 51, 40, 39, 48 o Serpentis, (see Miss Herschel's Cat. No. 100,)—3, 7, 9phiuchi,-o Oph. (66 Herculis ) The following is a sketch of the number of stars observed by Flanisteed; his Britannic Catalogue contains 2,935, of which 2,736 are completely observed; 64 imperfectly; 111* not observed at all; and 24 inserted twice, Besides which, his observations contain 371 of the first class, and 132 of the second. Total, 3,107 completely, and 196 imperfectly observed. AXTPOq IAOx.
* of these, the greater part donor exist,
Metrical Illustration of the
[March 1, To the Editor of the Monthly Magazine. SIR,
Can any one state the hour of the day 2 From one of twelve sides of a polygon 2 Twirl’d up by a spinning tetotum's play Curious ! that such duodecagon Shou'd life hour; not time hour youth and old age : As chance-life magicians wisely presage. Hopefull mathematical vagaries' Redeeming annuitants from their tombs, Just as the rate of interest varies: To revisit as oft their mothers wombs, And be new born: thus live, die, rise, and dance : To that strange Harmonist, blind-fiddler - chance, A silly nurse, may tell a timid child: “. Of ghosts alive, and walking in the dark; But must the manly mind be so beguil'd? That what it aims at; quite mistake the mark? not ghosts walk by day: as well as night? Why. o * darkness: and not knowa in t
The laying-down doctrine of De Moivre,
Makes the value of an annuity
On Life’s long or short continuity.
With a line
Errors on errors, hap-hazard must grow,
Grafted on such a will-o-wisp measure.
Together, that their products may becom? Joint lives co-tenures: are such equations!
That Chancers of Life shou'd learn to un
Joint-lives thus chanc'd algebraically;
make not life’s tether.