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

the small axis perpendicular to the ecliptic = 40''. sin. 30° = 20''. On October 13, the day of its conjunction with the sun, it stands in the outermost western part of the same to the right, on January 11 at the lowest or southern end of the small axis, on April 12, the day of the opposition, most eastward, and on July 12, most northward.

This change in the position of the stars in their aberration ellipse changes their longitude, latitude, right ascension, and declination. The amount of each of these changes can be determined by trigonometric calculations. For planets and comets, the effects of aberration are as great as the angle under which their motion—during the time it takes for light to travel from them to us—appears from Earth, and can therefore be easily calculated from their distances and movements.

Furthermore, the aberration of light has provided astronomers with a completely new and direct proof of the reality of the Earth's orbit around the sun, and has thereby confirmed the truth of the doctrines of Copernicus Nicolaus Copernicus, proponent of the heliocentric system in an unexpected way, see World System.

de la Lande, Astronomical Handbook §. 772 et seq. Smith’s System of Optics by Kästner, Book 4, Chap. 7, page 353. Bode, Explanation of Astronomy §. 615.

Arrester see Lightning rod.

Absolute is the name given to that which is considered purely in itself, and without reference to anything else similar. The relative, and sometimes the specific, is contrasted with the absolute. Examples of this can be found in the articles: Motion, Velocity, Weight, Force, Place, Gravity.

Absorbent, Absorbentia, Absorbants is the general name for all substances capable of combining with acids, e.g., alkalis and calcareous earths. Primarily, the latter, e.g., limestone, carry the