352 Description of a self performin gharrelorgan, [Oct. 



ened to the top board of the resei-voir L, and the other 

 end being attached to the weight, c. From this weight 

 another line passes over the pully, d, and the end of it is 

 fixed to the rod, e, which has a stop piece, f, at the bot- 

 tom, working against the edge of the fly wlieel, 8, [also 

 8 in figures 7, 8,]. Now it is evident that as the reser- 

 voir L rises, the weight, c, descends, and as the weight 

 descends, it pulls up the rod stop e, f, which working 

 against a part of the frame work of the organ, g, jams 

 or impinges against the edge of the fly, 8, and immedi- 

 ately stops it. It is also evident that as the reservoir L 

 sinks, the weight, c, rises, and the rod stop, e, f, being 

 left free, falls down by its own gravity, and releasing the 

 fly wheel 8, the machinery commences working; and is 

 thus made a perfect regulator of its own movements and 

 never permits the bellows to be overblown. The reser- 

 voir in fact, if I may speak figuratively, takes care of 

 itself, setting the bellows to work as soon as it requires a 

 supply of air, and stopping them as soon as it has 

 obtained it. 



15. — As it is necessary in an organ of this nature to 

 be able to stop it at pleasure when playing, and as this 

 Instrument has two separate pieces of machinery distant 

 and distinct from each other, it was requisite to contrive 

 some easy means of stopping both motions at once ; and 

 this was effected in the following manner. 



16. — Let the upper portion of figure 9, represent a 

 part of the mechanism of C in figure 1, i. e. of the organ 

 barrel movement~x, y, represent the fly [which carries 

 wings and is not like the fly wheel for the bellows] the 

 line,x; being a circular disk of thin brass: — w^, is a spring 

 with a rubber of leather at the end, pressing, when the 

 spring is released, on the diskxs. — u,is a rod attached to 

 the spring, which is lifted or depressed by means of the 

 excentric wheel t. Now the action of this arrangement 

 is, that when the excentric wheel, t, is turned in the 



