Eight British government expeditions for observing total solar eclipses were conducted by him between 1870 and 1905.
Among Lockyer's other works are - The Dawn of Astronomy (1894), to which Stonehenge and other British Stone Monuments astronomically considered (1906) may be considered a sequel; Recent and coming Eclipses (1897); and Inorganic Evolution (1900).
Firdousi accepted the challenge, and the three poets having previously agreed upon three rhyming words to which a fourth could not be found in the Persian language, 'Ansari began "Thy beauty eclipses the light of the sun"; Farrakhi added "The rose with thy cheek would comparison shun"; 'Asjadi continued "Thy glances pierce through the mailed warrior's johsun"; 1 and Firdousi, without a moment's hesitation, completed the quatrain "Like the lance of fierce Giv in his fight with Poshun."
A few latitudes had indeed been observed, but although Hipparchus had shown how longitudes could be determined by the observation of eclipses, this method was in reality not available for want of trustworthy time-keepers.
Ptolemy knew but of a few latitudes which had been determined by actual observation, while of three longitudes resulting from simultaneous observation of eclipses he unfortunately accepted the least satisfactory, namely, that which placed Arbela 45° to the east of Carthage, while the actual meridian distance only amounts to 34°.
The only phenomena of the sort available are eclipses of Jupiter's satellites, especially of the first.
Unfortunately these eclipses are not sudden but slowly changing phenomena, so that they cannot be observed without an error of at least several seconds, and not infrequently important fractions of a minute.
The zodiac was a Babylonian invention of great antiquity; and eclipses of the sun as well as of the moon could be foretold.
- The invention of this instrument has generally been ascribed, as in the ninth edition of this work, to the famous Neapolitan savant of the 16th century, Giovanni Battista della Porta, but as a matter of fact the principle of the simple camera obscura, or darkened chamber with a small aperture in a window or shutter, was well known and in practical use for observing eclipses long before his time.
It is believed to have been in use from the very time of its origin; for the observations of eclipses which were collected in Chaldaea by Callisthenes, the general of Alexander, and transmitted by him to Aristotle, were for the greater part referred to the beginning of the reign of Nabonassar, founder of the kingdom of the Babylonians.
John Goodricke established in 1782 the periodicity of its change in about 2 d 21 h, and suggested their cause in recurring eclipses by a large dark satellite.
The period of Algol, as measured by its eclipses, is subject to complex irregularities.
The alternate delay and acceleration of the eclipses are then merely apparent; they represent the changes in the length of the light-journey as the stars perform their wide circuit.
Inequalities of the required sort in the returns of the eclipses would ensue; moreover, their duration should concomitantly vary with the varying distance from periastron at the times of their occurrence.
I purpose to discourse with him concerning eclipses, for what is there which we may not hope for at his hands," and he also states " that he was wholly taken up and employed about the noble invention of logarithms lately discovered."
It contains an easy and accurate method for calculating eclipses; an essay on colour, in which three primary colours are recognized; a catalogue of 998 zodiacal stars; and a memoir, the earliest of any real value, on the proper motion of eighty stars, originally communicated to the Gottingen Royal Society in 1760.
On the Eclipses of Agathocles, Thales, and Xerxes," Phil.
It is remarkable that no records of eclipses are known from Egyptian documents.
It is remarkable that the discussion of ancient eclipses of the moon, and their comparison with modern observations, show only a small and rather doubtful change, amounting perhaps to less than one-hundredth of a second per century.
The notions of the penumbra and umbra are important in considering eclipses (q.v.).
25), and a great dragon or serpent is often the cause of eclipses, so that in India, on the occasion of an eclipse, its attention can be attracted by bathing in a sacred stream, or by a ritual which includes the worship of the image of the snake-god (i.
The generally recognized principal Avatars do not, however, by any means constitute the only occasions of a direct intercession of the deity in worldly affairs, but - in the same way as to this day the eclipses of the sun and moon are ascribed by the ordinary Hindu to these luminaries being temporarily swallowed by the dragon Rahu (or Graha, " the seizer") - so any uncommon occurrence would be apt to be set down as a special manifestation of divine power; and any man credited with exceptional merit or achievement, or even remarkable for some strange incident connected with his life or death, might ultimately come to be looked upon as a veritable incarnation of the deity, capable of influencing the destinies of man, and might become an object of local adoration or superstitious awe and propitiatory rites to multitudes of people.
In his investigation he employed the eclipses of the moon recorded in the Almagest, the Arabian eclipses between A.D.
800 and 1004, extracted from Caussin's translation of Ibn Junis, the eclipses and occultations of Bullialdus, Gassendi, and Hevelius, of the French astronomers at Paris and St Petersburg, and of Flamsteed at Greenwich, and deduced a secular acceleration of 8.8", agreeing well with the theoretical value.
Chrystal's Algebra, where also may be found details of the application of continued fractions to such interesting and important problems as the recurrence of eclipses and the rectification of the calendar.
But that native land was too far off, and for a man going a thousand miles it is absolutely necessary to set aside his final goal and to say to himself: "Today I shall get to a place twenty-five miles off where I shall rest and spend the night," and during the first day's journey that resting place eclipses his ultimate goal and attracts all his hopes and desires.