SUPPLEMENT
T O T H E
CTCLOP^DIA,
O R,
UNIVERSAL DICTIONARY
O F
ARTS AND SCIENCES.
A.
B, in the Hebrew chronology, the eleventh month of the civil year, and the fifth of the ecclefiaftical year, which begins with Nifau. The month Ab anfwers to the moon of July. This month had thirty days. Calmct,
ABACATUAIA, in zoology, the name of an American fifli, of the fhape of the European doree or faber. It is much of the fhape, fize, and figure of the common plaife. Its mouth is fmall and toothlefs, and its eyes have a black pupil, and a filvery iris. It lias five fins, one on the back, and another on the belly ; each running to the tail ; and two at the gills. The tail makes the fifth, and is confiderably forked. It has, befide thefe, two long filaments on the belly, and one fuch on the back, near the origin of the back-fin. It has no fcales, but is covered with a very fmooth and foft (kin. It is all over of a fine firming filvery white, except thefe filaments, which are perfeaiy black. It is caught about the fhores of the Brafils, and is commonly eaten there. See Tab. ofFifhes, N". ei. Margrave's Hilt. Braf.
AB ACA Y, in natural hiftory, a name given by the people of the Philippine illands to a fpecies of parrot, called alfo calan- gay. See Calangay.
AH A CI N ARE, or Abbacinare, in writers of the middle age, a fpecies of punifhment, confiding in the blind- ing of the criminal, by holding a red-hot bafon, or bowl before his eyes a .
The word is formed of the Italian bacino, a bafon ; though Menage choofes to derive it from the Italian bach, a dark or clofe place; the punifhment frequently going no farther, than to the diminifhing the fight b — [ ■ Du Cang. Gloff. Med. Lat. T. i. p. 2. Scboettg. Lex. Ant. p. 14.8. t V, Aqttin. Lex. Mil. T.I. p. 4. Crufc. T. I. p. 3. Voc. Abbacinare.]
ABACISCUS. See Abacus.
ABACIST, Abacista, in writers of the middle and bar- barous ages, denotes an arithmetician, or accomptant a
[" Du Cang. Gloff. Med. Lat. T. 1. p. 4. in Voc. Abacus. Crufc. T. 1. p. 3. Voc. Abbacbifta.]
A H A C O T, in our old writers, the antient coronet or cap of ftatc worn by our Englifh kings, made up in form of two crowns. Sprtm. Gloff. Arch. p. I.
AB ^CUS, (Cycl.)— or Abaciscus, in the antient ar- chitecture, is uied to denote certain compartiments in the uicruftation or lining of the walls of ftate-rooms, Mofaic pave- ments, and the like. Suppl. Vol. I. "
There were Abaci of marble, porphyry, jafper, alabaffer, of a even glafs; fhaped varioufly, fquare, triangular, and the like* — [" Vid. Plin. 1. 35. c. 1. Harduin. Not. ad Loc. Vitruv. 1. 7. c. 3. p. 133. Baxt. Gloff. Rom. p. 2. feq.] The Abacus for facilitating the operations of arithmetic, is an inftrument almoft as antient, and as extenfive, as the art of arithmetic itfelf : if it be later than the methods of computing by the fingers, and by lapilli, or ftones, (which obtained among the b Egyptians) 'tis at leaft much prior to the ufe of numeral letters, or figures, wrought with the pen.— ■ [ b Hcrodot. 1. 1. Hift. Acad. R. Infer. T. 3. p. 389.] We find it in ufe, under fome variations, among tire Greeks, Romans, Chinefe, Germans, French, he. It excells in point of facility, and cleanlinefs of operation, as working without any ffrokes, or blots of the pen, or wafte of paper ; fome alfo give it the preference in point of expedition : at leaft it ap- pears better adapted to the apprehenfion of children, and be- ginners in accounts, who might commodioufiy enough be firft initiated this way. Adam Riefe, who has written largely on the ufe of the Abacus, affures us he has found, in the teaching of youth, that thofe who begin with computing on the Abacus, become afterwards more dexterous and expert at accounts, than thofe who begin with figures. Wolf. Lex. Math. p. 171, Voc. Arithmetics.
The art of computing by the Abacus makes a peculiar fpecies of arithmetic, called calculatoria, or hgijiica per calculos ; by the French, la logijiiquc par jettons c . — [ c It is treated of by Herigon, in Curf. Mathem. P. 3. p. 125. & Dtcbales, in Mund. Mathem. T. 1. p. 412. feq. V. Wolf. lib. cit. p. 170.]
The Abacus is varioufly contrived ; that chiefly ufed in Euro- pean countries is made by drawing any number of parallel lines, at pleafure, at a diftance from each other, equal to twice the diameter of a calculus, or counter. Here a counter placed on the firft or lowermoft line fignifies 1 ; on the fecond, 10 ; on the third, 100 ; on the fourth, 1000 ; on the fifth, 10000 ; and fo on. In the fpaces between the lines, the fame counters fig- nify half of what they fignify on the next fuperior line ; viz. in the fpace between the firft and the fecond lines, 5 ; between the fecond and third, 50 ; between the third and fourth, 500 ; and fo on. Thus the counters on the Abacus, in the figure here fubjoined, make the fum of 37392.— The Abacus is alfo divided crofs-wife into Areolar, by means whereof fubtradfions are made. Wolf. Lex. Math. p. 171. feq.
1 B' 10000
