We use Optical Character Recognition (OCR) during our scanning and processing workflow to make the content of each page searchable. You can view the automatically generated text below as well as copy and paste individual pieces of text to quote in your own work.
Text recognition is never 100% accurate. Many parts of the scanned page may not be reflected in the OCR text output, including: images, page layout, certain fonts or handwriting.
8 not, however, perfectly uniform. The orbits in which they revolve are not circular, but oval or elliptical, so that they are nearer to the sun in some parts of their course than they are in others; and when they are nearest the Sun, they revolve more rapidly than when they are more distant from him. The orbits of Comets are very long ellipses (Diag. XIII.) so that the dis- tance of these bodies from the Sun, and their rate of motion in different parts of their orbits, vary extremely; but the orbits of the Planets generally approach the circular form much more closely (some of them depart- ing from it very little), and there is, consequently, much less inequality in their rate of motion in different parts of their orbits. It is to Kepler that we owe the discovery of the elliptical orbits of the planets ; and also of the very simple law which governs their rate of movement. This law is explained by DIAGRAM IIT. which represents an ellipse, of which the points F and S are the foci; the line P to P 6 drawn through these foci to the two extremes of the ellipse is called its long diameter; whilst a line A B passing through its centre C at right angles, is called its short diameter. The more nearly the foci of an ellipse approach each other, the less will be the difference between the long and the short diameters, and the more closely will the ellipse approach the circular form. On the other hand, the more distant the foci are from each other, the greater will be the difference between the long and the short diameters, and the more long and narrow will be the ellipse. The more widely the orbit departs from the circular form, the greater is said to be its eccentricity. The position of the Sun is not in the centre C, but in one of the foci S. When the planet or comet is in the part of the orbit nearest to it, as at P, it is said to be in perihelion ; but when it is in the most distant part of its orbit, P 6, it is said to be in aphelion. Now, a