Dictionary of Physics or an Attempt at an Explanation of the Most Important Concepts and Technical Terms of Natural Philosophy

Chalk, crab's eyes, burnt bones, and the like bear the name of absorbent materials. When these materials contain a bound gas, an effervescence occurs upon their combination with acids.

Distance see Removal.

Distance from the Zenith, Distantia a vertice, Distance au Zenith.

The arc of a vertical circle contained between the zenith point or zenith and a star or other point in the sky. Since the zenith is everywhere 90° away from the horizon, the distance of a star from the zenith always makes up 90° with its altitude, or: the distance from the zenith is the complement of the altitude. If, for example, the altitude of a star is 55°, its distance from the zenith will be 35°.
The sun has the smallest distance from the zenith at noon on the longest day, and the largest at noon on the shortest day. The former amounts to 27° 51' 33'' for Leipzig, the latter to 74° 47' 49''.

Distance of the Equinox from Noon, Distantia aequinoctii a Sole, Distance de l'equinoxe au soleil ou au meridien,

is called in astronomy the number of degrees or hours that the vernal equinox point has yet to traverse from the moment of noon before it reaches the meridian.
This distance of the equinox from noon is, expressed in degrees, always 360° less the right ascension of the sun. Suppose, for example, the right ascension of the sun is 90°, or the sun arrives at the meridian at the same time as the 90th degree of the equator; then, at the moment this happens, the vernal equinox or the beginning of the equator will be 90° further toward the evening, and will therefore still have 270° to travel before it completes the whole circle and thus enters the meridian again the next time. Therefore, its distance from noon is 270° = 360° — 90°.
If one wishes to express this distance in time, then