The Average price is 18 £ and each bomb of 18 £ Value is of a power to do as much execution as a fire ship which costs 2 or 3 thousand; 6,660 of them may be made for 120 thousand pounds or the first cost of one first rate Ship of the line when engines of such destructive powers can be multiplied to so great a degree, and at an expence which cannot be felt by an opulent nation the practice of them may produce novel and serious consequences. [Illustration: PLATE THE NINTH ] In cases where a nation commands the seas as in the present state of the British marine, the Seamen can approach sufficiently near the Enemy’s harbours and roadsteads to use such engines from common boats; by which means several hundred Bombs with instantanious Locks might be anchored in the passages leading to the Texel, Havre, Brest or other ports of the Enemy which would render it impossible for any Vessel to move in or out. But it may be said that the Enemy are already completely blockaded and England has no need for such a mode of war; this I admit, but this mode is less expensive than the Usual method of Blockading and destressing an Enemy’s commerce; yet should the economy not be thought of importance Still this invention has to be considered in another point of View, and that of the most interesting kind, Which is; how would it affect the commerce and marine of England had the French the means of anchoring 20 or 20 thousand such Bombs in the channels to the Thames in the Bays, Harbours, Roadsteads, and a long the coast of England, scotland or Ireland; I will now endavour to Shew what an Economic simple and certain means this would give to France to totally destroy the British Marine And First as to Economy, The Boulogne Flotilla has cost the french treasury more than three millions Sterling, for this sum, more than Two hundred thousand instantanious Bombs might be made; with such a Magazine at Boulogne or Calais and 100 good row boats the Enemy might each dark night throw some hundreds of Bombs in the channels of the Thames in the Downs or along the coast, to the total destruction of the British Commerce, _And if her commerce cannot be protected what is the use of her Marine?_ I will now Shew that were this Simple System organized in France, it is not in the power of the whole British marine to prevent the practice of it to any extent which Bonapart might desire, and he certainly would desire the annihilation of the British Marine,—