More than one of these 7 encyclopedias carries each of the following subjects — but every one of them treats it in a sentence or two and then moves on. They are gathered here so the different accounts can sit side by side.
Atomic Theory
Collier's New Encyclopedia: a theory, first propounded by John Dalton in his "New System of Chemical Philosophy," published in 1807. He stated that the atoms of each element were incapable of being subdivided, and each had a definite relative weight, compared with that of hydrogen as 1; that hat the composition of a definite chemical compound is constant; that if two elements, A and B, are capable of uniting with each other in several proportions, the quantities of B, which unite with a given quantity of A, usually bear a simple relation to one another. Dalton supposed that one element replaced another atom for atom, but it has since been found that one atom of an element can replace one or more atoms of another element, according to their respective atomicities.
Aiton's Encyclopedia: . See Chemistry
Covered by Collier's New Encyclopedia and Aiton's Encyclopedia
Atreus
Collier's New Encyclopedia: the son of Pelops and Hippodamia. He and his brother Thyestes murdered their half-brother Chrysippus, from jealousy of the affection entertained for him by their father. Thereupon, they fled to Eurystheus, with whose daughter Ærope, Atreus united himself, and, after the death of his father-in-law became King of Mycene. Thyestes seduced the wife of his brother and had two sons by her. Atreus, after the discovery of this injury, banished Thyestes with his sons. Thirsting for revenge, Thyestes conveyed away secretly a son of his brother, and instigated him to murder his own father. This design was discovered, and the youth, whom Atreus thought to be the son of his brother, was put to death. Too late did the unhappy father perceive his mistake. He pretended to be reconciled to Thyestes, and invited him, with his two sons, to a feast; and after he had caused the latter to be secretly slain, he placed a dish made of their flesh before Thyestes, and, when he had finished eating, brought
1000 Classical Characters: A son of Pelops and Hippodamia , was king of Mycenae . His brother Chrysippus was of disgraceful birth, and Hippodamia wished to get rid of him, and urged Atreus and another of her sons, Thyestes, to murder him, which, on their refusal, she did herself. Atreus retired to the court of Eurystheus , king of Argos, and succeeded to his throne.
Covered by Collier's New Encyclopedia and 1000 Classical Characters
Atropos
Collier's New Encyclopedia: the eldest of the Fates, who cuts the thread of life with her shears. ATTACHÉ ATTACHÉ (at-a-sha), a military, naval or subordinate member of the diplomatic service attached to an embassy or legation.
Aiton's Encyclopedia: at'ro-pos, in Greek mythology, the eldest of the Fates. It was the part of Atropos to sever the thread of human life. See Fates
Covered by Collier's New Encyclopedia and Aiton's Encyclopedia
Atys
Aiton's Encyclopedia: or Attys, or Attis, in Phrygian mythology, a beautiful youth beloved by the goddess Cybele. Cybele's father Maeon caused his death. According to another account, he was faithless to Cybele and was about to marry another, when the angry goddess appeared and dispersed the wedding guests, driving Atys into the mountains, where he committed suicide. In either case, he was supposed to have met death by a pine tree which received his spirit, while from his blood sprang violets. Cybele was famed to have made long and frantic search for him. Atys was made memorable in the spring worship of Cybele. A pine tree garlanded with violets was brought to Cybele's shrine, then a three days, search was made among the mountains, the worshipers giving expression to frantic grief, accompanied with the wildest music of drums, fifes, and cymbals. On the third day Atys was found, and then extravagant rejoicing succeeded the mourning. The finding of Atys is supposed to symbolize the revival of nature in spring. The legend has its counterpart in the Greek story of Aphrodite and Adonis. See Cybele
Collier's New Encyclopedia: or ATTYS (at'is), in classical mythology, the shepherd lover of Cybēle, who, having broken the vow of chastity which he made her, castrated himself. In Asia Minor Atys seems to have been a deity, with somewhat of the same character as Adonis.
Covered by Aiton's Encyclopedia and Collier's New Encyclopedia
August
Aiton's Encyclopedia: the eighth month of the year. Beginning the year with March the Romans called August Sextilis, or the sixth month. Quintilis, or the fifth, was renamed July, in honor of Julius Caesar. The Roman senate renamed the sixth month, August, in honor of Caesar's successor, the Emperor Augustus. August had originally but thirty days; July had thirty-one; so an additional day was added to August in order that the month of Augustus might not seem inferior in any respect to the month named in honor of Julius Caesar. This is one reason why the months of the year are so unequal in length, it being impossible to give them all thirty-one days apiece. In the north temperate zone August is preeminently the month of harvest. It is a winter month in Tasmania.
Collier's New Encyclopedia: the name given to the eighth month of our year. It was named B. C. 30, by the Roman Emperor Augustus, after himself, as he regarded it as a fortunate month for him, being that in which he had gained several important victories. Before this time it was called Sextilis, or the sixth month, the year beginning with March. The name of July had, in like manner, been Quintilis, before it was changed by Julius Cæsar; and as it contained 31 days, the Senate, in order that Augustus might not be behind Cæsar, decreed that August also should have 31 days, and that, for this purpose, a day should be taken away from February.
Covered by Aiton's Encyclopedia and Collier's New Encyclopedia
Aurochs
Aiton's Encyclopedia: a'roks, the wild ox of Europe. It was once abundant in the forests of Europe, but has been hunted until only a few herds, under protection, are now left in Lithuania and in the Caucasus Mountains. It resembles the American bison or "buffalo" closely, but is a trifle larger and less shaggy. The fore and hind quarters of the aurochs are also unequal. See Bison ; Buffalo 2026 Editor's Note: The entry has muddled two animals: the beast it describes, still surviving in Lithuania, was really the European bison (wisent). The true aurochs — the great wild ox, ancestor of all domestic cattle — had been extinct since 1627, when the last cow died in a Polish forest. Scientists now try to 'breed it back' from cattle for rewilding projects. (Ed: BR 2026-06-05)
Collier's New Encyclopedia: the English and very nearly the German name of the aurochs fossile of Cuvier, the bos irus of some other writers, now called bison priscus. It belongs to the order ruminantia and the family bovidæ. It is a species of ox, with a shaggy coat and mane, found by the Romans in the forests of Germany and Belgium, and still existing in small numbers in Lithuania.
Covered by Aiton's Encyclopedia and Collier's New Encyclopedia