Although bell music is not of a favourite kind, yet, for the benefit of such clockrnakers as may be disposed to construct music clocks, and have not the opportunity of getting the music pricked on the barrel by those whose profession it is to do this sort of work, we shall give a de scription of the tool and its apparatus, which will be found very well adapted for this purpose, and also of the manner of using it.
Having a good strong turn-bench, such as those used by clockmakers for their larger sort of work, to the standards or heads of it let there be attached supports on each side ; to the supports on the side nearest the workman, let there be fixed a straight cylindrical rod AB, about ten or twelve inches long, and in diameter a quarter of an inch, or even three-tenths of an inch. A spring socket CD must be made for this rod to slide easily and steadily along it, some what like the socket which slides on the upright stalk or rod of a watchmaker's glass stand. In the thick and strong part of this socket E is fixed a steel arm EFG, bent intoa i curve, which lies over and above the music barrel when in the tu•n-bench, as shewn in Plate CCCVILL Fig. 2. at EFG. The steel rod AB may at pleasure be placed at any distance from the barrel, about an inch or rather more, and should stand parallel to the barrel arbor MN, and nearly in the same plane with it, but rather a little above this than otherwise. On the outer end of the curved arm is fixed a i flat piece of steel G, a little more than half an inch long, in breadth not quite so much, and about one-tenth of inch thick. The lower and front edges of this fiat piece steel should be neatly and smoothly rounded off, so as to allow it to come easily and freely into the notches a, b, c, &c. which are on the edge of a thin brass scale, whose use will come afterwards to be explained. To the supports at tached to the turn-bench heads, and on the opposite side to that where the round steel rod is placed, let there be fixed a slip of brass XY, about ten or twelve inches long, an inch and a half broad, and nearly a tenth of an inch thick, the inner edge of which must be made to stand parallel with the barrel, and the flat side to stand nearly in a plane between the upper surface of the barrel ancUits centre, the edge being placed so as to stand clear of the tops of the teeth of a high numbered wheel W W screwed on to the end of the barrel. Near the ends of this slip of brass slits arc made, through which screws s, s, pass that screw it to the upper side of the supports ; the slits serving to allow it to be moved a little occasionally lengthwise when re quired. On the upper side of the slip of brass is fixed an other, but not quite so thick, the length being about that of the bat rel, and breadth one inch and three quarters. On
the inner edge of this are made as many notches a, b, c, fx.c..as there are hammers, bells, or notes, to be used in the tune or tunes to be marked on the barrel. These notches are equidistant, and the middle of them should correspond to the middle or line of the hammer tails ; their width be ing such as to admit the flat steel piece G on the end of the curved arm. EFG ; the depth of them cut on the edge of the hrass should be about one quarter of an inch. The edge of this piece of brass, or music scale as it may be called, must also stand parallel with the barrel, and at a lit tle distance from it, not nearer than three-tenths of an inch, so that the flat steel piece on the end of the curved arm may have room to get in a little way, and to pass through at the same time to a cetain degree of depth. On the upper side of this brass slip the letters of the scale of music or gamut are marked to those notches•which corre spond with the hammer tails, and hammers intended to strike on the bells the notes so marked, but in an inverted order to the usual way in which they are marked in the scales of music, the lower notes being on the right hand side, and as they rise going to the left. This is done to suit the way in which the bells are commonly, though not necessarily, placed in music clocks (See Plate Fig. 3 ) ; for a clockmaker of any ingenuity might contrive the barrel to turn any way he thought proper, and place the bells to stand in the order of the music scale, if there was any advantage to be derived from it. In the curved arm EFG, Fig. 2. is fixed a punch f, having a very fine and sharp conical point, at the distance of four inches or so from the centre of the sliding socket, and not quite an inch from the outer end of the flat steel piece ; the punch when applied to the barrel should stand upright, and directly over the centre of it. This apparatus being all adjusted as we have directed, it is evident that, when the curved arm is raised up a little way, the socket can then be made to slide easily along the steel rod, and by this means bring the out er end of the flat steel piece very readily into any notch required, and the point of the punch is brought at the same time with the greatest precision to the place of the note on the barrel, leaving the flat steel piece for the time in the notch : The point of the punch touching or resting on the barrel, a stroke from a very small hammer on the top of it will cause the point to make a pretty deep mark or conical hole on the stn face of the barrel.