The following specification is for a small turret clock which will strike on a l 1/4-cwt. bell. Going barrel, G in. in diameter and 16 in. long; main wheel, 10in. in diameter, one hundred and twenty teeth. The hour wheel had forty teeth, is 3 1/3 in. in diameter, and runs with the main wheel; the second wheel, driven also from the main wheel, has a pinion of ten leaves, is 8 in. in diameter, and has one hundred and twenty teeth; the 'scape wheel (dead beat) is driven by the second wheel, has a pinion of eight leaves, is 4 1/2n. in diameter, and has thirty teeth: striking barrel, 7 in. in diameter, 16 in. long; main wheel, eighty teeth, diameter 12 in.; second wheel (carries eight cams for lifting the striking hammer), 8in. diameter, eighty teeth, pinion of twenty leaves; third wheel (carries a cam upon which the striking lever rests), 6 in. diameter, eighty teeth, pinion of ten leaves; fly (carries the locking arm), pinion of ten leaves. The locking plate or count wheel is mounted on a stud outside the frame, and is driven by a pinion of eight leaves fixed to the axis of the cam wheel or second wheel. The locking-plate wheel has seventy-eight teeth. The fly has two vanes, each Sin. by 4in., the centres of which are 12 in. from the axis.

The main wheel of the going train revolves once in three hours; the second wheel once in fifteen minutes; the 'scape wheel once in one minute. The cylindrical bob of the seconds pendulum is of cast iron, weighing about 701b. The going weight will probably be about 1/2cwt. or a little more, falling about 24ft.on a double line"for a four days' run. The striking weight should be about I 1/2 cwt., falling about 20ft. on a double line for a four days' run. The clock can be made to go for a week by increasing the weights, putting them on triple lines, and giving about a 30-ft. fall. The frame should be A-shaped, with the going train up the right-hand side and the striking train up the left. The pendulum should hang in the middle of the frame from the top and swing between the barrels. The back 'scape pivot must be held by a cock to clear the pendulum rod. The arbors of the wheels run in gunmetal bushes screwed on to the sides of the frame, and each is detachable separately. The striking pinion, cams, barrels, main wheels, and second wheel may be of cast iron; all other wheels should be gunmetal, and all other pinions, lanterns.

The bell hammer should weigh about 31b. The pendulum, if not compensated, should have a deal rod, round, lin. thick.

The wood minute hand is poised by a short outside counterpoise, and the hour hand by an inside weight.