126 Dr. Cutbush on the Chinese Fire, fyc. 



Chinese fire, in cases, is commonly employed for gar-", 

 nishing, as it is called, the exterior circumference of a 

 decoration in fire works, or in forming pyramids, gallerieSp 

 yewtrees, cascades, palmtrees, and in short a variety of fig- 

 ures arrayed according to taste and fancy. Small cases 

 are often employed in turning pieces for their last fire, in 

 consequence of the superior brilliancy of the flame. It 

 forms in its descent flowers of variegated beauty, which being 

 scattered about by the rotation of the piece, to which it is 

 attached, resembles the pyro-hydraulic girandole in the 

 rays of rhe sun. In porportion to the velocity of which, the 

 flame is more perfect. 



There are certain compositions, commonly denominated 

 white-Jire, which are used in cases, and give motion to wheels 

 and the like. This motion is on the rocket principle, and 

 depends on the propelling power (gaseous products,) of 

 the inflamed matter acting against a resisting medium, 

 namely, the atmosphere. Chinese fire, however, possesses 

 in this respect but little force ; and hence when it is used in 

 rotatory works, it is accompanied with two or more jets or 

 cases of white fire. Cases charged with chinese fire, 

 when burnt alone, will not communicate motion to a wheel. 

 As the effect of Chinese fire on wheels, to the periphery of 

 which the cases are usually fixed, depends greatly on the 

 motion given to the wheel, its velocity should therefore be 

 accelerated; which although the duration of its effect 

 would be shorter, but more brilliant, may be produced by 

 employing several cases of white fire, and communicating 

 their fire one to the other by means of quick match in the 

 usual manner. 



The accelerated motion, thus given, would cause the com- 

 position to burn with more rapidity, in the same manner as a 

 bellows would excite the heat of a furnace, and necessarily 

 produce a more rapid oxidizement of the metal, as well as 

 a more rapid combustion of the other ingredients 



We may remark here, that with respect to the compara- 

 tive force of compositions or that power by vvhich rock^ 

 ets, &c. ascend, or which imports motion to vertical and 

 horizontal wheels, it depends on the nature of the compq- 

 sitions, and the recoil in such instances is proportionate 

 to the impelling power; for the resistance which the fire 

 meets from the air. in the immediate vicinity of the calibre 



