As it is now demonstrated that the Earth is a plane, the distance of the Sun and Stars may readily be measured by plane trigonometry. The base line in any operation being horizontal and always a carefully measured one, the process becomes exceedingly simple. Let the altitude of the Sun be taken on a given day at 12 o’clock at the high-water mark on the sea shore at Brighton, in Sussex; and at the same hour at the high-water mark of the River Thames, near London Bridge; the difference in the Sun’s altitude taken simultaneously from two stations upon the same meridian, and the distance between the stations, or the length of the base line ascertained, are all the elements required for calculating the exact distance of the Sun from London or Brighton; but as this distance is the hypothenuse of a triangle, whose base is the Earth’s surface, and vertical side the zenith distance of the Sun, it follows that the distance of the Sun from that part of Earth to which it is vertical is less than the distance from London. In the Diagram, Figure 26, let L B represent the base line from London to Brighton, a distance of 51 statute miles. The altitude at L and at B taken at the same moment of time will give the distance L S or B S. The angle of altitude at L or B, with the length of L S or B S, will then give the vertical distance of the Sun S from E, or the place which is immediately underneath it. This distance will be thus found to be considerably less than 4,000 miles. [Illustration: FIG. 26.] The following are the particulars of an observation made, a few years ago, by the officers engaged in the Ordnance survey. Altitude of the Sun at London 55° 13′; altitude taken at the same time, on the grounds of a public school, at Ackworth, in Yorkshire, 53° 2′; the distance between the two places in a direct line, as measured by triangulation, is 151 statute miles. From these elements the true distance of the Sun may be readily computed; and proved to be under 4,000 miles! Since the above was written, an officer of the Royal Engineers, in the head-quarters of the Ordnance Survey, at Southampton, has furnished the following elements of observations recently made:-- Southern Station, Sun’s altitude, 45° Northern ditto, „ „ 38° Distance between the two stations, 800 statute miles. The calculation made from these elements gives the same result, viz., that the actual distance of the Sun from the Earth is less than 4,000 miles. The same method of measuring distances applies equally to the Stars; and it is easy to demonstrate, beyond the possibility of doubt, so long as assumed premises are excluded, that all the visible objects in the firmament are contained within the distance of 6,000 miles!