WATCH. 



I 



the pendant's axis, which, by being turned to the right or 

 left, will catife either the hours or quarters to ftrike firft, 

 according to the direftion of motion ; and pins inferted into 

 the plane of the rim, at the fide oppofite to the indentation, 

 lift the hammer-tail to flrike as many blows as the hour and 

 quarter notches made on the inner edge of the rim, and aft- 

 ing with the fecond arms of the detents, refpeftivcly deter- 

 mine. In this mechanifm, a chain wound round a barrel 

 containing a fpring, and fixed on the pillar- plate, brings the 

 fteel rim back again to its original fituation, which entirely 

 depends on the pofition of the fnails. 



A patent was taken out for a repeating watch by the fame 

 ingenious man, dated 30th Oftober, 1806 ; but as we have 

 not feen the defcription thereof, we are unable to fay how it 

 differs from either of thofe which we have juft defcribed. 



Berrollas' Repeater. — Jofeph Anthony BerroUas of Den- 

 mark -ftreet, in the parilh of St. Giles in the Fields, London, 

 took out a patent for what he calls an infallible repeating 

 watch, bearing date 31ft Odober, 1808, of which watch 

 we (hall give a brief defcription in this place. In the plate 

 to which we lad referred. Jig. 6. fhews the repeating portion 

 of BerroUas' watch, in a ilate of aftion ; _^^. 7. (hews the 

 calliper of the common movement, hammer, and ring ufed 

 for the bell ; and the detached pieces of the repeating por- 

 tion are reprefented fingly in the group of Jig. 8. Like 

 Elliot, Berrollas founds his pretenfions to pubhc approba- 

 tion on the fimplicity of his contrivance, and on the confe- 

 quent cheapnefs, where the repeating motion by wheels and 

 pinions is difpenfed with, and where one hammer only is ne- 

 ceffary for ftriking both the hours and quarters. Thoygh 

 we have not feen the watch we now undertake to defcnbe, 

 et as it has fome peculiarities in its conftruftion, not quite 

 o intelligible as could be wifhed in the defcription given in 

 the Repertory of Arts, vol. xiv. p. 364, we will venture to 

 deviate a little from the author's own account. The 

 outfide of the watch refembles common watches, except in 

 the pendant, which is mounted with a button, confifting of 

 two parts, C and X : the lower one, X, does not move, 

 and the upper one, C, having an endlefs fcrew annexed to 

 it, turns round and comes out to the extent of four turn?, 

 and is cut into four turns and a half. The upper part of 

 the button G, being turned to the right, fcrews off from 

 the lower part X, and operating upon the hour-rack A, 

 can be continued to be unfcrewed until it has flruck the 

 hour which the hand indicates, when it cannot be further 

 unfcrewed. The fame part C, being afterwards fcrewed to 

 the left, to bring it back again to join the lower fixed part 

 X, operates upon the quarter-rack B, and quarters are 

 ftruck in the fame manner as the hours, until the part C is 

 completely joined to the part X. The piece W draws 

 piece B back to its former flation. The motion is com- 

 pofed of three principal parts, A, B, and C : A contains 

 the hour-rack, B the quarter-rack, and C the pendant and 

 endlefs fcrew. The piece C, turning on itfelf, afccnds per- 

 pendicularly, and is kept in a proper direftion by the piece 

 E, which performs two objcfts. The interior of it forms 

 the catch-work of the fcrew, whilft the exterior is fixed by 

 two fcrews on the pillar-plate ; and when the piece C is 

 turned, it afts upon the piece A, and gives it a circular 

 motion, firft by means of the piece D D, whofe interior is 

 caught in the notch at the extremity of the piece C, while 

 the exterior part of it is caught in the piece A ; fecondly, 

 by the piece F, which holds the piece D D in a groove ; 

 tTiirdly, by the piece G, which is fixed to the pillar-plate 

 with three fcrews, and under which the piece A is fixed by 

 mean* of a pivot, on wliich it moves. The piece A, being 

 thus moved, catches by means of twelve teeth, cut in its in- 



13 



terior part, the piece H, which puts ia aftion the ham- 

 mer Q, that ftrikes on the bell-fpring R, fixed to the pillar- 

 plate S, as feen in fig. 6. 



The piece A panes under the piece K, which is a brafs 

 bar with two fcrews to keep piece A from rifing. In 

 order to give a free and a fteady motion to the piece A, it 

 is operated upon by a pivot faftened to a fpring U, placed 

 on the infide of the pillar-plate ; which pivot, pamng tlu'ough 

 a hole in the pillar-plate, caufes a fteady fridlion under the 

 teeth of the piece A. The piece A is regulated by the ftar N 

 and hour-fnail M, in the common way, with a jumper and 

 fpring, when the hours are ftruck ; alfo the quarter-fnail P, 

 the quarter-piece B, and its fpring O, regulate the fame, when 

 the quarters are ftruck, through the agency of the forked 

 piece J, which is on the fame arbor as the tail-piece H and 

 hammer. The tooth V, on the piece A, falls on one of 

 the fteps of the hour-fnail, and determines the number of 

 ftrokes for the hours, when A is turned one way round, 

 and the heel-piece of the quarter-piece near P falls on the 

 quarter-fnail, when the motion is given to A in the contrary 

 direction, and thus determines the ftrokes given for the 

 quarters, while two fprings keep the tail-pieces H and J in 

 their refpeftive places ; one of which fprings, L, is feen 

 upon the plate, and the other is faft to the piece K, not 

 feen. Thus the ilriking in this watch is produced by 

 manual prefTure, as is done in Elliot's watches, and the me- 

 chanifm differs from that at the rooms of the Adelphi 

 Society only in thefe refpetts : — that the motion is produced 

 by a fcrew, inftead of a pinion ; and the piece A moves 

 round a pivot at the end of the cock G, inftead of being 

 formed into an exaft ring to move within friftion-roUers. 



Alarum, 'larum, or ivarning IVatch. — The watches which 

 we have above defcribed under the denomination of repeating 

 watches, can be ufeful only to pcrfons who are awake, 

 and, therefore, do not anfwer the purpofe of giving pre- 

 vious notice of the approach of any particular hour and ipi- 

 nute, at which it may be required to be roufed from fleep. 

 This purpofe is ufually effected by a 'larum clock ; but we 

 will now defcribe how the fame thing has been done by fome 

 additions to a pocket-watch. We will firft defcribe the 

 former method of adding the warning mechanifm to a 

 watch, and then explain the conftruftion lately adopted by 

 Berrollas, and fecured to himfelf by a patent. The old 

 'larum watch has been fo well defcribed by Berthoud, in 

 the firft volume of his " Hiftoire de la Mefure du Tems," 

 p. 66, &c. that we cannot do better than give a fimilar 

 drawing and defcription, after omitting his account of the 

 ordinary movement. 



In the frame of the watch a fpring-box is made faft to 

 the under fide of the upper-plate, and has a great wheel, 

 ratchet, and click, to wind up by ; but the winding is per- 

 formed by the key inferted on the fquare end of the fpring- 

 arbor, while the box remains at reft. When the great wheel 

 is made to revolve by the ratchet, it drives two other wheels 

 and pinions, which, with it, conftitute the warning train, 

 and is in every refpedl fimilar to a repeating train, except 

 that there is an efcapement-wheel inftead of a fly. This 

 train, therefore, will be the more eafily underflood, from 

 our preceding defcription of the ftriking or repeating train. 

 Fig.9<. of Plate XLVI. exhibits fo much of the warning 

 mechanifm as appears on the exterior face of the upper-plate, 

 and will fuffice to explain the conftruftion and aftion of all 

 the eftential parts, if we bear in mind that a part of the 

 warning train and the fpring-box are within the frame, of 

 which this plate forms the cover. The arbor of the con- 

 cealed fpring-box is feen at A, bearing a finger that afts 

 with three teeth cut in the femicircle of the circular piece F, 



pivotted 



