FIRES OF DIFFERENT COLOURS. 



confine ourselves (o what has been here said, and refer the reader 

 to the author's memoirs, which will be found in the Manuel de 

 VArtifider. 



The saltpetre, pulverised gunpowder, and charcoal, are three 

 times sifted through a hair sieve. The iron sand is besprinkled 

 with sulphur, after being moistened with a little brandy, that (he 

 sulphur may adhere to it; and they are then mixed together : the 

 sulphured sand is then spread over the 6rst mixture, and the whole 

 is mixed with a ladle only ; for if a sieve were employed, it would 

 separate the sand from the other materials. When sand larger thau 

 that of the second order is used, the composition is moistened with 

 brandy, so that it forms itself into balls, and the jets are then 

 loaded ; if there were too much moisture, the sand would not per. 

 form its effect. 



SECTION T. 



Of Fires of different Colours. 



IT is much to be wished that, for the sake of variety, different co. 

 lours could be given to these fireworks at pleasure ; but though we 

 are acquainted with several materials which communicate to flame 

 various colours, it has hitherto been possible to introduce only a 

 very few colours into that of inflamed gunpowder. 



To make white fire, the gunpowder must be mixed with iron or 

 rather steel filings. 



To make red fire, iron sand of the first order must be employed 

 in the same manner. 



As copper filings, when thrown into a flame, render it green, it 

 might be concluded, that if mixed with gunpowder, it would pro. 

 duce a green flame; but this experiment does not succeed. It is 

 supposed that the flame is too ardent, and consumes the inflam- 

 mable part of the copper too soon. But it is probable that a suffi- 

 cient number of trials have not yet been made; for is it not possible 

 to lessen the force of gunpowder in a considerable degree, by in. 

 creasing the dose of the charcoal ? 



However, the following are a few of those materials which, in 

 books on pyrotechny, are said to possess the property of commit, 

 nicating various colours to fireworks. 



Camphor mixed with the composition, makes the flame to appear 

 of a pale white colour. 



