These rockets are peculiarly fitted for asteroids, as, from their lightness, they rise to great heights, with immense rapidity, not in a continuous curve, of uniform flexure, but with a sweeping serpentine motion, as indicated by the line, fig. 164. They might be employed, with great advantage, for distress rockets at sea.

They could also be made with four wings, and fired in volleys, from batteries constructed with square tubes. See the design, fig. 165.


[LIST OF PRICES.]

[CONCLUDING REMARKS.]

Sublimation is the volatilization of solid substances by heat, and their crystallization by cold again into solids.

The products of sublimation (sublimates) have received the name of flowers from their soft efflorescence, or aggregation of minute spicular crystals into flakes; as flowers of sulphur, the crystallized refrigerated vapour of burning brimstone; flowers of benzoin, benzoic acid; corrosive sublimate, bichloride of mercury; sublimed arsenic, camphor, sal-ammoniac; vegetable and lamp black, the condensed fumes of burning oils and resins; soot, the flakes deposited in chimneys from the smoke of burnt wood and coals.