ROL 



This neceflary duty is performed by the lerjeants of com- 

 panies, morning and evening, in every well-regulated corps. 

 Hence we have "morning roll-call," and " evening roll-call," 

 on critical occafions ; and in fervices that require prompti- 

 tude and exertion, frequent roll-calls (hould be made. 



Roll, Calves-bead, is a roll in the two Temples, in 

 which every bencher is taxed yearly at 2s., every barrilter 

 at is. 6d., and every gentleman under the bar at u. to the 

 cook, and other officers of the houfe, in conlideration of a 

 dinner of calves-heads, provided in Eafler term. 



Roll, Ragman's, or RagmuntPs Roll, is a roll denomi- 

 nated from Ragimund, a papal legate in Scotland ; who, 

 callino- before him aLl the people who held benefices in that 

 kingdom, caufed them, upon oath, to give in the value of 

 their eftates, according to which they were taxed in the 

 court of Rome. 



Rolls, or Office of Rolls, in Chancery-lane, London, is 

 an office appointed for the cuftody of the rolls and records 

 in chancery. 



The matter of this office is the fecond perfon in that court ; 

 and, in the abfence of the lord chancellor, he fits as judge. 

 See Master of the Rolls. 



This houfe, or office, was anciently called Domus Con- 

 ■terforum, as being appointed, by king Henry III., for the 

 ufe of converted Jews ; but their irregularities occafioned 

 king Edward II. to expel them thence : upon which, the 

 place was deputed for the cultody of the rolls. 

 Rolls, Clerk of the. See Clerk of the Rolls. 

 Rolls, or Roul, tmong Military Men. See Roll. 

 Roll, Bead. See Bead-/??//. 

 Roll, Check. See Check-RoII. 

 Roll, Counter. See Counter-/?o//. 

 Roll, in Antiquity. From the time of Anaftafius, we 

 find in the hands of the emperors, on medals, a kind of 

 narrow long roll, or fachel ; the meaning of which has 

 greatly puzzled the antiquaries. 



Some imagine it to be a roll or bundle of papers, me- 

 moirs, petitions, &c. prefented occafionally to princes, 

 confuls, and the like. Others take it to be a plaited haud- 

 kerchief, which the perfons who prefided at the games call 

 forth as a fignal for their beginning. Others will have it a 

 bag of duft and allies, prefented the emperor at the cere- 

 mony of his coronation, and called akakia, q. d. a means of 

 preferving innocence, by the remembrance of duft, &c. 



Roll, or Roller, is alfo a piece of wood, of a cylindrical 

 form, ufed in the conftruftion of feveral machines, and in 

 feveral works and manufactures ; though fometimes under 

 other names. 



It is on fuch rolls, properly called beams, that the woollen, 

 filken, and other threads are wound., of which the weaver's 

 works confift. For which end, each loom has ufually 

 'wo, and that of the gauze-weavers three. 



In the glafs manufacture, they have a running-roll, being 

 «> thick cylinder of call brafs, ferving to conduft the melted 

 glafs to the end of the table, on which large looking-glafles 

 are to be call. 



The founders alfo ufe a roller to work the fand which 

 they ufe in making their moulds. 



The preffes called calenders, as ferving to calender (tuffs, 

 iconfift, among other effential parts, of two rollers. 



It is alfo between two rollers that the waves are given to 

 filks, mohairs, and other ituffs proper to be tabbied. 



Prints, or impreffions, from copper-plates, are alfo taken 

 by palling the plate and the paper between two rollers. See 

 Rolling-prefs Printing, and CoppER-Plate Work. 



Rolls, in Coining, are two iron inftruments, of a cylin- 

 drical figure, which ferve to draw or ftretch out the plates 

 9 



ROL 



of gold, filver, and other metals, of which the planks of 

 pieces are to be formed for the fpecies. 



Rolls, in Printing, are two large cylinders or barrels of 

 wood fattened in the middle of what they call the cradle or 

 gallows of the prefs ; and which, by means of a cord or 

 girt palling over each, and a handle which gives motion to 

 one of them, draw the carriage of the prefs backwards and 

 forwards. See Printing. 



Rolls, in the Sugar-Works, are two large iron barrels, 

 which ferve to bruife the canes, and exprefs the juice. They 

 are call hollow, and their cavities are filled up with wood, 

 the cylinders of which are properly the rollers. 



Rolls, or Rollers, among Carpenters, Mafons, &c. are 

 plain cylinders of wood, feven or eight inches in diameter, 

 and three or four feet long ; ufed for the removing of beams, 

 huge (tones, and other like burden;-, which are cumberfome. 

 but not exceedingly heavy. 



Thefe rollers are placed, fucccfiively, under the fore-part 

 of the mafl'es to be removed ; which, at the fame time, are 

 pufhed forward by levers, &c. applied behind, 



Rolls, Endlefs. When blocks of marble, or other ex- 

 ceffive heavy loads, are to be removed, they ufe what they 

 call endlefs rolls. 



Thefe, to give them the greater force, and prevent their 

 burlting, are made of wood joined together by crofs-quar- 

 ters ; they are about double the length and thicknefs of the 

 common roller, and, befides, are girt with feveral large iron 

 hoop3 at each end. At a fuot's diftance from the ends 

 are four mortifes, or rather only two, but pierced through 

 and through, into which ?.re put the ends of long levers 

 which the workmen draw by ropes faitened to the ends, (till 

 changing the mortife, as the roll has made a quarter of a 

 turn. 



RoLL-r/VA Stones, in Antiquity, a feries of huge (tones, 

 ranged in a circle, near Morton in the Marfh, in Oxford- 

 fhire. There are many fabulous traditions about them. 

 Among the antiquaries, fome take them to be a monument 

 of a viftory ; others, a burying place ; and others, a place 

 for the coronation of the Danifh kings. 



Near Penros, in Cornwall, is a like monument. 



ROLLAND, in Geography, an ifland in the South In- 

 dian fea, difcovered by Kerguelen in the year 1773, fo 

 called by him after the name of the veflel in which he failed ; 

 about nine miles in circuit. N. lat. 48° 37'. E. long. 68" 



43'- 



ROLLE, Michael, in Biography, a French mathema- 

 tician, was born at Ambert, a fmall town in Auvergne, in 

 the year 1652. His father was in rather low circumdances, 

 and placed him to gain his livelihood, at firft with a notary, 

 and afterwards with different country attornies. Difgulted 

 with an occupation fo little fuited to his genius, at the age 

 of 23 he went to Paris, depending for his fupport on hit 

 penmanfhip. At firft he taught writing and the early rules 

 of arithmetic : from arithmetic he advanced by gradual 

 fleps to algebra, to which he became fo enthufiaftieally at- 

 tached, that he fpent every leifure moment in the ftudy till 

 he became diftinguifhed in that branch of fcience. In 1682, 

 the learned Ozanai-n having propofed a difficult mathema- 

 tical problem to exercife the ingenuity of mathematicians, 

 M. Rolle fent him a very clear folution of it, together with 

 methods which he had invented of folving other problems, 

 attended with (till greater difficulty. The minifter Colbert, 

 always the patron of talent, having heard of Rolle, deter- 

 mined to draw him out of the oblcurity in which he had 

 hitherto been concealed, and fettled on him a penfion. H« 

 now gave up the occupation of a writing malter, and de- 

 voted himfelf entirely to the ftudy of algebra, and the 



other 



