g4} ^J^ THE COST dy MAKING tKOSPHORlTS-^ 



New ftriking D. The fpiral work of the wheel A. The black fpoti 

 part of a clock, q^^^^, ^^iq grooves into whicii the detents drop, on ftriking 

 the hour. 



E. The groove into which the locking piece F drops, 

 when it ftrikes one, and from which place it proceeds to 

 the outward parts of the fpiral in the progre Tive hours, be- 

 ing thrown out by a lifting-piece H, at each hour; the 

 upper detent G being pumped off with the locking-piece F, 

 from the pins in the wheej A . 



In ftriking the hour of tzvehe, the locking-piece, having 

 arrived at the outer fpiral at H, rifes up an inclined plane, 

 and drops by its own weight to the inner circle, in which 

 the hour one is to be flruck, and proceeds on in a progreffive 

 motion through the different hours till it comes again to j 

 twelve. M 



J. The hammer-work made in the common way, which ■. 

 is worked by thirteen pins, on the face of the fpiral. 



Fig. 2. — K. The thirteen pins on the face of the fpiral, 

 which work the hammer-work. 



L. The outer pins, which lock the detent. 



M. The pump-fpring to the detent. 



VI. 



On the Cnft of making Phojphorus. In a Letter from J. P. 



To Mr. NICHOLSON. 



SIR, 



Brijiol, September 16, 1804. 



XJlAVING lately been led io confider the various procefTes 

 by which phofphorus might be oblained, with a view to deter- 

 in Ine the moft eligible, I thought that a very ihort fketch of 

 what had occurred to me on the fubjeft, might be not im- 

 properly introduced in a fpare corner of your Journal; if you 

 fiiould be of that opinion, the contents of the following pages 

 are much at your fervice, from a very refpedful admirer of 

 your unremitting exertions in the caufe of Science and Phib" 

 fophy. 



J. p. 



I. In 



( 



