ATH 



10k 



AT O 



desert of Atac'an.a, in Peru. Primitive 

 foiiu, octohedron. 



A'TAR. When the petals of roses are 

 immersed in water and distilled, there 

 separates a small portion of frasrrnnt bu- 

 tyraceous oil, which liquefies by heat, and 

 appears yellow, but concretes in the cold 

 into a white mass. This is called atar of 

 roses, and is highly prized as a perfume. 



ATELES, nttM,;, irritiis, imp'rjtctu*. 

 Hrande has it, " A genus of South Ame- 

 rican monkeys, characterised by the 

 absence of the thumb of the anterior 

 hand, for the want of which they are 

 sufficiently compensated by a very effi- 

 cient-prehensile tail." 



ATELI.Y'NA; FAUULJE, a species of co- 

 medy, which originated among the Oscan 

 inhabitants of Campania, from the town 

 Atella, which gave it its name. 



A TEMPO GifsTo. (In temjwre justo). 

 An Italian phrase used in music to signify 

 in equal time, or just time. A tempo, at 

 the same time. 



ATEN'CHUS, a genus of pentamerous cole- 

 optcra, two of the species of which were 

 worshipped by the ancient Egyptians, and 

 form a conspicuous feature in their system 

 of hieroglyphics. They were also figured 

 on all their monuments, and separately 

 on the most precious metals, and were 

 used as seals and as amulets, which were 

 suspended to the neck, and buried with 

 the mummies. Atenchi are also found in 

 gome of their coffins. One of the species, 

 A., tacer, is an object of superstitious dis- 

 tinction, even in Europe. 



ATHAL'AMOUS, Gr. from at, without, and 

 6>MfAs, a bed. Lichens whose thallus is 

 not furnished with shields or beds for the 

 spores, but whose reproductive matter is 

 supposed to be dispersed through the ab- 

 sence of the crust, as in l-.-p^aria. 



ATHAMAK'TA, a genus of European per- 

 ennials, of which the Candy carrot 

 'brought from the island of Candy), and 

 the black mountain parsley, used in me- 

 dicine, are species. Pentandria Digynia. 

 Named from the country of the Atha- 

 mantes, in Epirus. 



ATHA.NA'SIAN CREED, the exposition of 

 faith composed by Hilary, bishop of Aries 

 (430), and formerly attributed to Athana- 

 aius, bishop of Alexandria. 



A'THEISM, from , without, and 0ej, 

 God. The doctrine which teaches the 

 non-existence of a Supreme Intelligent 

 Being. Opposed to theism and deism. As 

 a manner of thinking with regard to re- 

 ligion, it is the opposite of faithand. belief. 



ATHE'N.UM. A&ivawov- In antiquity, 

 1. The school which Adrian established 

 on the Capitoline Mount. 2. A gym- 

 nasium at Athens. In modern times, a 



name given to different establishments 

 connected with literature or the sciences. 



ATHEWC'ZRA, afamily of dipterous bi- 

 sects in the system of Cuvier, general!/ 

 found on foliage, comprehending th 

 modern families Syrphidse. Astridae, Co- 

 nopidae, and Muscidae. Name from <*(&, , 

 acute, and xi, a horn. 



ATHEIU'NA, a genus of abdominal fishes, 

 the b*st known of which, Hep.-etus, is 

 found abundantly in the Mediterranean. 



ATHER'OMA, I 0egfl,o of attend, pap. 



ATHERO'ME, J An encysted tumour, 

 which contains a substance of a pulpy 

 consistence. 



ATHLE'T^E, combatants who took part in 

 the public games of Greece, and made 

 wrestling and boxing their business. 

 From etiS^of, contest. 



ATHWA'KT (from a and twert, traverse}, 

 in nautical language, across the line of a 

 ship's course. Athwart ships, reaching 

 across the ship from side to side, or in 

 that direction. 



ATHWA'RT-HAWSE, the situation of a 

 ship when she is driven by the wind, 

 tide, or other accident, across the fore- 

 part of another. Athwart the fore-fuot, 

 denotes the flight of a cannon-ball from 

 one ship across the course of another to 

 intercept that other, and make lier 

 shorten sail. 



ATLAN'TIDES. 1. In astronomy, the 

 Pleiades (q.T.). 2. In arrhitecture, sta- 

 tues of men used to support entablature* 

 with mutules, otherwise called aUam. 



AT'LAS. 1. In the Greek mythology, a 

 Titan condemned by Jupiter to tear the 



vault of heaven. 2. In anatomy, the 



first vertebra of the neck which supports 

 the head, as Atlas did the heavens '. 



3. A collection of maps to which a pic- 

 ture of the fable is usually prefixed. 



4. In commerce, a beautiful silk manufac- 

 ture of the East Indies. 5. In architec 



ture, see ATLANTIDES ^2nd def.). 



ATMOM'ETER, from U.T/LM;, vapour, and 

 f^iT^tu, to measure. An instrument con- 

 trived by Sir J. Leslie to measure the 

 quantity of vapour exhaled from a humid 

 surface in a given time. 



AT'MOSPHERE, from artto? , vapour, and 

 trQotiQot, a sphere. The body of air which 

 surrounds the earth. (See AIR.) In a 

 wider sense, it is that mass of elastic 

 fluid with which any body is surrounded. 

 Hence we speak of an atmosphere of the 

 sun, of the moon, of electric bodies, &c. 

 Atmosphere, one, two, &., means a pres- 

 sure of lolbs., 30 IDS., &c., on the square 

 inch, resulting from condensation. The 

 force of steam, weight of flu.ds, &c., are 

 often so estimated. 



AT'OM, ATO/&O; (from at, not, and r.= a4> 

 to cut), one of the elementary particles 01 

 matter, and so small as to be incap iWe ot 

 further division. See MOLECULE anJ COR- 



