THE 



GALLERY 



OF 



NATURE AND ART. 



PART II. 



ART. 



BOOK II. 



PYROTECHNY, or the ART of CONSTRUCTING 

 FIRE-IVORKS. 



CHAPTER I. 



CONSTRUCTION OF THE CARTRIDGES OF ROCKETS. 



XX.OCKETS may be regarded as the grand basis of all fire-works, 

 which are little more than modifications of their form, and of the 

 materials of which they usually consist. A rocket is a cartridge 

 or case made of stiff paper, which being filled in part with gun. 

 powder, saltpetre, and charcoal, rises of itself into the air, when 

 fire is applied to it. 



There are three sorts of rockets : small ones, the calibre of which 

 does not exceed a pound bullet ; that is to say, the orifice of them 

 is equal to the diameter of a leaden bullet which weighs only a 

 pound ; for the calibres, or orifices of the moulds or the models 

 sed in making rockets, are measured by the diameters of leaden 

 bullets. Middle sized rockets, equal to the size of a ball of from 

 one to three pounds. And large rockets, equal (,o a ball of from 

 three to a hundred pounds. 



