ness at the CRUCIFIXION of our SAVIOUR was not occasioned by an Eclipse of the Sun. For he suffered on the day on which the PASSOVER was eaten by the JEWS, namely, the third day of April, A. D. 33: on that day, it was impossible that the Moon's shadow could fall on the Earth's. Eor the Jews kept the PASSOVER at the time of full Moon ; nor does the darkness in total Eclipses of the Sun, last above four minutes and six seconds in any place; whereas the darkness at the CRUCIFIXION lasted three hours, and overspread, at least, all the Land of JUDEA.

2

SECTION EIGHTEENTH.

ON THE FIXED STARS.

THE Stars are said to be fixed, because they have been generally observed to keep at the same distances from each other; their apparent diurnal revolutions being caused solely by the Earth's turning on its axis. They appear of a sensible magnitude to the eye, because the retina is affected, not only by the rays of light which are remitted directly from them, but by many thousands more, which, falling upon ́our eye-lids, and upon the aerial particles about us, are reflected into our eyes so strongly, as to excite vibrations, not only in those points of the retina, where the real images of the stars are formed, but also in other points of some distance round. This makes us imagine the Stars to be much larger than they would appear, if we saw them only by the few rays which come directly from them, so as to enter our eyes, without being intermixed with others. Any person may be sensible of this, by looking at a Star of the first magnitude, through a long, narrow

tube, which, though it takes in as much of the sky as would hold a thousand such stars, yet scarcely renders that one visible.

The more a telescope magnifies, the less is the aperture through which the star is seen; and consequently the less number of rays it admits into the eye. The stars appear less in a telescope which magnifies 200 times, than they do to the naked eye; insomuch that they seem to be only indivisible points; it proves at once that the stars are at immense distances from us, and that they shine by their own proper light. If they shone by reflection, they would be as invisible without telescopes, as the satellites of Jupiter. These satellites appear larger when viewed with a good telescope, than any of the fixed stars.

The number of stars discoverable in either hemisphere by the unaided sight, is not above a thousand. This at first, may appear increditable: because they seem to be almost innumerable, but the deception arises from our looking confusedly upon them without reducing them to any order: look steadfastly upon a large portion of the sky, and count the number of stars in it, and you will be surprised to find them so few. Consider only how seldom the Moon's passes between us and any star, (although there are as many about her path, as in any other parts of the Heavens ;) and you will soon be convinced that the stars are much thinner sown, than you expected. The British catalogue, which, besides the stars visible to the naked eye, includes a great number which cannot be seen, without the assistance