Q U 289 



piece, till the pluiiib line rest at the degree of elevation 

 requin 



QUA 



See ALGEBRA, VoL I. 



Description of Mr Irvine's xul>xliiutc J'ur the Gunner's 



(luudrunt. 



As one of the objects of the Gunner's Quadrant is 

 to point guns precisely in the same manner when the 

 visual line does not bear on the object, and when the 

 object aimed at is hit by the gun at a particular eleva- 

 tion ; the following instrument, which answers the pur- 

 pose much better, was contrived by Alex. Irving Esq. 

 Tvhen first Lieutenant of the Edinburgh Corps of Artil- 

 lery. It is represented in a front and back view in Fig. 

 15. and 16'. The following is Mr. Irving's own descrip- 

 tion of it. " Breadth of the aperture, one inch ; length, 

 one and a half, which is divided by a scale, into 18 parts, 

 each of which, when the length of the gun (this calcu- 

 lation applies to the ordinary light six-pounders) is made 

 radius, will be equal to five minutes. The Nonius di- 

 viding plate which is fixed to the horizontal move- 

 able wire, being divided into five parts, which altoge- 

 ther are equal to four divisions of the scale, will give a 

 division into minutes. 



The two feet of the instrument rest upon the upper 

 part of one of the muzzle mouldings of the gun, on 

 which it is kept by a steel spring. The spirit level 

 must be parallel to the line joining the feet, and at 

 right angles to the vertical wire. The view of the 

 back part will show the mode in which the Nonius 

 and horizontal wire are raised and lowered by means 

 of a screw. 



The aperture is bisected vertically by a black wire, 

 which is cut at right angles by a horizontal wire. The 

 latter, however, must not be a wire, but a thin plate 

 set edgewise, that it may bear being raised or lowered. 

 When it arrives at the opposite side of the instru- 

 ment, it is flattened in a contrary direction, and kept 

 close to the limb of the instrument by a slip of metal, 

 which, however, allows it to move freely up and down. 

 In using the instrument, says Colonel Macdonald, 

 the horizontal wire can be depressed or elevated till 

 its intersection with the perpendicular one cuts some 

 point on the object, and, by bringing the intersecting 

 point on the same part of the object in all succeeding 

 shots, the gun will be always similarly pointed. The 

 angle of elevation of field-pieces seldom exceeds the 

 degree which that instrument is capable of ascertain- 

 ing, and it might easily be rendered capable of mea- 

 suring larger angles than are usual in field service. 

 See Colonel Macdonald's work On Projectiles, Fuzes, 

 $c. pp. 59, CO. Lond. 1819. 



For farther information on the subject of Quadrants, 

 see Bion on the Construction and Principal Uses of Ma- 

 thematical Instruments ; Smith's Optics, vol. ii. chap. 

 vii. p. 332 ; " The Method of Constructing Mural 

 Quadrants," published by order of the Commissioners 

 of the Board of Longitude, in the year 1768 ; Vince s 

 Treatise on Practical Astronomy ; Grandjean de Fou- 

 chy's Machine for Managing a Quadrant, in the Mem. 

 Acad. 1740, p. 468; or Machines Approuvees, vii. p. 4~. 

 A quadrant with a reflecting Telescope is described in 

 the Mem. Acad. Par. 1746, Hist p. 121 ; Gersten's 

 Quadrantis Muralis Idea Nova, in the Phil. Trans. 

 1747, vol. xliv. p. 507 ; Pouchy on Converting a 

 Quadrant into an Azimuthal Instrument, in the Mem. 

 Acad. Par. 1781, p. 259 ; Caesaris de Quadrantc Mit- 

 rali Mediolanensi Ramsdeni, 8vo. See SEXTANT. 



VOL. XVII. PART I. 



QUADRATIC EQUATIONS. 



QUADRATURE. See GEOMKTBY, VoL X. p. 221. 



and FLUXIONS, Vol. IX. p. 447. 



\UHUPEDS. -ITALIA. 



\KKHS, or FJUKNDB. The tenets more pecu- 

 liarly held* by this society were firt promulgated by 

 George Fox, about the year 1 647. He, on this account, 

 often suffered persecution. In the year 1650 he wa 

 imprisoned at Derby, and it was here that the name of 

 QUAKERS was first given to George Fox and his 

 friends, by one of the Justices who committed him, 

 becouse he had bid them to " tremble at the word of 

 the Lord." This appellation soon became, and has 

 since continued to be, their usual denomination ; but 

 they themselves adopted the appellation of FRIENDS. 



During the time of the Commonwealth much per- 

 sonal abuse was bestowed on them ; imprisonment was 

 common ; and stripes, under pretence of vagrancy, 

 were inflicted without regard to sex, and on persons 

 of unimpeachable character, and of good circumstances 

 in the world. Although the practice of inflicting cor- 

 poral punishment on this people seems in England to 

 have fallen into disuse at the restoration, yet the reign 

 of Charles II. must be considered as the time of their 

 greatest suffering. Their imprisonments were long, 

 often terminating only with the life of the prisoner. 

 The crowds shut up together increased, in many places, 

 the ordinary sufferings of confinement; which, in 

 some cases, were augmented by the barbarity of gaol- 

 ers. The fines imposed were exacted with a rigour 

 that generally oppressed the sufferer, and sometimes 

 left him nearly destitute of household goods; and 

 several families experienced a separation of the nearest 

 connexions of life, by the execution of a law which 

 subjected the members of this society to banishment. 

 The king, as a branch of the legislature, joined in the 

 enactment of these laws ; nevertheless, he did not seem 

 in all cases to countenance severity, for he was the 

 means of affording relief in the most sanguinary perse- 

 cution which the Friends ever experienced. This was in 

 New England, where it was made penal for a Quaker 

 even to reside. The government of that province first 

 imprisoned them, next employed the scourge, which 

 was followed up by cutting off their ears ; but all this 

 proving insufficient to deter the Friends from return- 

 ing to New England in order to preach the Gospel, 

 which they believed to be a duty required of them by 

 the divine will, a law was enacted to banish them on 

 pnin of death. Their constancy, however, was not 

 thus to be shaken, and four Friends, one of whom was 

 a woman, were hanged at Boston. In this extremity, 

 application was made to Charles II. who willingly 

 granted his mandamus, dated 9 l h September, l66l, to 

 stop these severities. The Quakers, in common with 

 other dissenters, were relieved by the suspension of 

 the penal laws under James II. But it was not until 

 the reign of King William that they obtained any de- 

 gree of legal protection. In the year 1681 Charles II. 

 granted to William Penn the province of Pennsylvania. 

 Penn's treaty with the Indians on this occasion, re- 

 flects honour on his memory, and forms a striking con- 

 trast with the conduct of other colonists. In the go- 

 vernment which he formed, he allowed that full liberty 

 of conscience, which he and his friends had themselves 

 claimed from their fellow-professors of the Christian 

 name. If the Independents have the credit of being 

 the first who held the principles of toleration, the 

 J o 



