ECLIPSE, the deprivation of the light of the sun, or of some heavenly body, by the interposition of another heavenly body between our sight and it. Thus, eclipses of the sun happen by the moon's intervening between it and the earth ; by which means the shadow of the moon falls upon the earth, when the latitude of the moon does not prevent it, by ele vating the moon above, or depressing it below the earth. On the other hand, an eclipse of the moon can only happen when the earth is interposed between the sun and it ; for then, if the latitude of the moon does not prevent it, the sha dow of the earth may fall on the moon, and thereby cause either a partial or to tal eclipse. A total eclipse of the sun or moon is when their whole bodies are ob scured ; and a partial one is when part only of their bodies is darkened : again, a central eclipse is when it is not only total, but the eclipsed body passes through the centre of the shadow. See ASTRONOMY.
As total solar eclipses are by no means common, we shall give an interesting de scription of one, by Dr. Stukeley, sent to his friend the celebrated Dr. Edmund Halley.
" According to my promise, I send you what I observed of the solar eclipse, though Ifear it will not be of any great use to you. I was not prepared with any instruments for measuring time or the like, and proposed to myself only to watch all the appearances that nature would present to the naked eye upon so remarkable an occasion, and which gene rally are overlooked, or but re garded. I chose for my station a place called Haradon Hill, two miles eastward from Amsbury, and full east from the opening of Stonehenge avenue, to which it is as the point of view. Before me lay the vast plain where that celebrated work stands, and I knew that the eclipse would appear directly over it ; besides, I Vad the advantage of a very extensive prospect every way, this being the high est hill hereabouts, and nearest the mid dle of the shadow ; full west of me, and beyond Stonehenge, is a pretty copped hill, like the top of a cone, lifting itself above the horizon ; this is Clay-hill near Warminster, 20 miles distant, and near the central line of darkness, which must come from thence, so that I could have notice enough before hand of its approach.
Abraham Sturgis and Steven Ewens, both of this place, and sensible men, were with me. Though it was very cloudy, yet now and then we had gleams of sunshine, rather more than I could perceive at any other place around us. These two per sons, looking through smoked glasses, while I was taking some bearings of the country with a circumferentor, both confidently affirmed the eclipse was be gun, when by my watch I found it just half an hour after 5 ; and, accordingly, from thence the progress of it was visi ble, and very often to the naked eye, the thin clouds doing the office of glasses. From the time of the sun's body being half covered, there was a very conspicu ous circular iris round the sun, with per fect colours. On all sides we beheld the shepherds hurrying their flocks into fold, the darkness coming on ; for they ex pected nothing less than a total eclipse for an hour and a quarter.
" When the sun looked very sharp like a new moon, the sky was pretty clear in that spot ; but soon after a thicker cloud covered it, at which time the iris vanished, the copped hill before mentioned grew very dark, together with the horizon on both sides, that is to the north and south, and looked blue ; *1st as it appears in the east at the de clension of day. We had scarce time to tell, then, when Salisbury steeple six miles offsouthward became very black ; the copped hill quite lost, and a most gloomy night with full career came upon us: at this instant we lost sight of the sun, whose place among the clouds was hitherto sufficiently distinguishable, but now not the least trace of it to be found, no more than if really absent : then I saw. by my watch, though with diffiulty, and only by help of some light from the northern quarter, that it was 6 hours 35 minutes: just before this the whole corn pass of the heavens and earth looked of a lurid complexion, properly speaking; for it was black and blue, only in the earth upon the horizon the blue prevail ed; there was likewise in the heavens among the clouds much green interspers ed,,so that the whole appearance was really very dreadful, and as symptoms of sickening nature.