684 



PYROTECHNY 



was kindled commonly by other fire-works, which seemed to end in their play, by pro- 

 jecting the serpent from the bosom of the flames. The motion was communicated to 

 the chain by one of the wheels, which received it like a clock from the action of a 

 weight. This remarkably curious mechanism was called by the artists a salamander. 

 The rockets which rise into the air with a prodigious velocity are among the most 

 common, but not least interesting, fire-works. When employed profusely they form 

 those rich volleys of fire which are the crowning ornaments of a public fete. The car- 

 tridge is similar to that of other jets, except in regard to its length, and the neces- 

 sity of pasting it strongly, and planing it well ; but it is charged in a different manner. 

 As the sky-rockets must fly off with rapidity, their composition should be such as to 

 kindle instantly throughout their length, and extricate a vast volume of elastic fluids. 

 To effect this purpose, a small cylindric space is left vacant round the axis ; that is, 

 the central line is tubular. The fire- workers call this space ' the soul of the rocket ' 

 (tame de la fusee). On account of its somewhat conical form, hollow rods, adjustable 

 to different sizes of broaches or skewers, are required in packing the charge ; which 

 must be done while the cartridge is sustained by its outside mould, or copper cylinder. 

 The composition of sky-rockets is as follows : 



The cartridge being charged as above described, the pot must be adjusted to it, with 

 the garniture ; that is, the serpents, the crackers, the stars, the showers of fire, &c. 

 The pot is a tube of pasteboard wider than the body of the rocket, and about one- 

 third of its length. After being strangled at the bottom like the mouth of a phial, it 

 is attached to the end of the fusee by means of twine and paste. These are afterwards 

 covered with paper. The garniture is introduced by the neck, and a paper plug is 

 laid over it. The whole is enclosed within a tube of pasteboard terminating in a 

 cone, which is firmly pasted to the pot. The quick-match is now finally inserted into 

 the soul of the rocket. The rod attached to the end of the sky-rockets, to direct their 

 flight, is made of willow or any other light wood. M. Ruggieri replaced the rod by 

 conical wings, containing explosive materials, and thereby made them fly farther and 

 straighter. 



The garnitures of the sky-rocket pots are the following : 



Stars are small, round, or cubic solids, made with one of the following compo- 

 sitions, and soaked in spirits. White stars: nitre, 16; sulphur, 8; gunpowder, 3. 

 Others more vivid consist of nitre, 16 ; sulphur, 7 ; gunpowder, 4. 



Stars for golden showers: nitre, 16; sulphur, 10; charcoal, 4; gunpowder, 16; 

 lamp-black, 2. Others yellower are made with nitre, 16 ; sulphur, 8 ; charcoal, 2 ; 

 lamp-black, 2 ; gunpowder, 8. 



The serpents are small fusees made with one or two cards ; their bore being less 

 than half an inch. The lardons are a little larger, and have three cards. The ret 'dies 

 are smaller. Their composition is, nitre, 16; charcoal, not too fine, 2; gunpowder, 

 4 ; sulphur, 4 ; fine steel-filings, 6. 



The petards are cartridges filled with gunpowder and strangled. 



The saxons are cartridges clayed at each end, charged with the brilliant burning 

 fire, and perforated with one or two holes at the extremity of the same diameter. 



The cracker is a round or square box of pasteboard, filled with granulated gun- 

 powder, and hooped all round with twine. 



Roman candles nro fusees which throw out very bright stars in succession. With 



