AGO 



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ACQ 



ACOXITA, a poisonous vegetable- princi- 

 ple extracted from aconitutn. 



ACONITE, the herb wolf's bane, particu- 

 larly the species monk's- hood (aconitum 

 napellus). 



ACONITINE, the narcotic principle of the 

 aconite. It is uncrystallisable, alkaline, 

 Inodorous, little soluble in water, but 

 readily so in either alcohol or ether. It 

 combines with the acids, and forms un- 

 cnrstaliisable salts. It may be obtained 

 eiiht-r in a granular white substance, or 

 as a colourless transparent mass having a 

 glassy lustre 



ACONITUM, wolfs bane ; a genns of hardy 

 perennial plants, containing about forty- 

 five species, most of which are poisonous. 

 Class polyandria, order trigynia. Locality, 

 all countries of Europe. Name> axoviTov, 

 from oxofouu, o f O.KUV, a dart, because 

 the ancients used its J'^ice for the purpose of 

 poisoning their darts. 



AcoN'riAS (afOKTia?, from CIKOVTIOV, 

 a dart). 1. A species of African serpeut 

 called dartsnake, or jaculum, from its 



manner of darting on its prey. 2. A 



comet or meteor resembling the serpent. 



ATOMIC (IKO.TIKOS), preventing or re- 

 medying weariness. 



A'coB, Lat. from aero, to be sour. Aci- 

 dity ; sourness in the 'stomach. 



ACC/RIA, from a<cooo<?, not satisfied. 

 Canine appetite; a diseased desire for 

 food or drink. 



A'CORN, the fruit of the oak ; an oral 

 nut which grows in a rough permanent 

 cup. Name, from Sax. aec, or ac, oak, 

 and corn, a grain. 2. In nautical lan- 

 guage, a small ornamental piece of wood 

 of a conical shape, fixed on the point of 

 the spindle above the vane, on the mast 

 head, to keep the vane from being blown 



off. 3. In conchology, the lepas, a genus 



of shells of several species found on the 

 British coasts. The shell is multivalvular, 

 unequal, and fixed by a stem. It is always 

 found fixed to some solid body. 



A'CORCS, aromatic calamus, sweet flag 

 or sweet rush or sedge. A eeuus of hardy 

 perennial plants of three species, belong- 

 ing to the class hexandria, and order 

 monogynia. Name, aKOpos. from topr), 

 the pupil of the eye, from its being sup- 

 posed good for disorders of the eyes. 

 There. Is only one British species, common 

 in the middle and south-eastern counties I 

 of England, and watery places on the ' 

 banks of rivers, *c. 2. In natural his- 

 tory, a blue coral found on the coasts of 

 Africa. It grows in the form of a tree on 

 a rocky bottom. 



ACOTYLK'DON, from a, without, and 

 Kt)TV\t,6iav. A plant whose seed is not 

 furnished with lobes or cotyledons. In j 

 the uatural system of Jussieu, the acoty- 



letlnna form a class which correspond! 

 j with the cryptogam!* of Linnssus. 

 ! ACOTY LE'DONOUS, nt having cotyUdont, 

 or seed lobes. 



| ACOCMETER, from aKOVta, to iear, and 

 | fJifTpov, a measure. An instrument for 

 estimating the extent of the sense of 

 hearing. 



i ACOUSMATICS. Acou<r/L(.irriKOi. In 

 anti'iuitiet, disciples of Pythagoras, who had 

 not finished their five yean of probation. 

 ! ACO'USTIC, from OKOVOTI.KO<;, (from 

 j aicovta, to hear). Relating to hearing: 

 Acoustic duct, in anatomy, the meatus 

 auditorius, or external passage of the ear. 



Acoustic nerve, the portio mollis, the 



immediate or^au of hearin -. An acoustic 

 medicine is one used far disorders of the 

 sense of hearing. Acoustic instruments, 

 such as produce, convey, or concentrate 

 t sound, e. g. the speaking trumpet. Acoustic 

 | vessels, in ancient theatres, were brazen 

 [ tubes or vessels shaped like a bell, to 

 propel the voice of the actors, so as to 

 render them audible at a great distance. 

 i . ACOUSTICS, the science which treats of 

 I the natu-e, phenomena, and laws of 

 1 sound. The science is sometimes divided 

 | into diacoustics, which explains the pro- 

 J perties of sounds coming immediately 

 I from the sonorous body to the ear : and 

 | catacoustics, which treats of reflected 

 sounds. 



Sound is the result of vibratory mo- 

 tions produced in bodies, and trans- 

 mitted to the ear through the air (or 

 any other body in cont.tct with the ear). 

 The intensity increa-es or diminishes 

 as the elasticity of the air increases or 

 diminishes. If the impulses from the 

 sonorous body be repeated continuously, 

 and at shorter intervals than the ear 

 can attend to them individually, tone is 

 produced, and this is grave or sharp, 

 according as there are many or few in 

 a given time. The sudden termination 

 of the impulses produces noite. The 

 shock which causes the sensation of 

 sound spreads somewhat as a wave 

 spreads in water, with a strength de- 

 creasing in the inverse ratio of the 

 square of the distance. The velocity is 

 usually estimated at 1142 feet per second, 

 but the latest experiments make it 

 1120 feet. Sound is reflected from 

 smooth surfaces, hence echoes, &c. 

 ACQUEST. Lat. acquisitut. In law, some- 

 thing acquired by purchase, in contradis- 

 tinction to what is acquired by inherit- 

 ance. 



ACQUIREMENT, from acquire, Lat. ac- 

 quiro. Something attained, and which 

 is in a degree permanent. It denotes 

 especially personal attainments, In oppo- 

 sition to material or external things 

 gained, which are more usually called 



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