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of Cornwallis; but I do not believe that we either of us thoughtof him when we drew up our respective addresses.

About this time application was made to me by government,to know whether I could give any advice relative to the improve-ment of the strength of gunpowder; and I suggested to them themaking charcoal by distilling the wood in close vessels. Thesuggestion was put in execution at Hythe, in 1787, and the im-provement has exceeded my utmost expectation. Major-GeneralCongreve delivered to me a paper, containing an account of theexperiments which had been made with the cylinder powder, (socalled from the wood being distilled in iron cylinders,) in all ofwhich its superiority over every other species of powder was suf-ficiently established. In particular, a given quantity of gunpowder,made with this kind of charcoal, threw a ball of sixty-eight poundsweight two hundred and seventy-three feet; whilst the samemortar, at an equal elevation, and charged with an equal weightof gunpowder made with charcoal prepared in the best of theordinary ways, threw an equal ball only one hundred and seventy-two feet. In this experiment, the strength of the cylinder, esti-mated by the horizontal range, is to that of the best sort of otherpowder, as 100 to 63. By experiments with the Eprouvette, theproportion of the strength of the cylinder to other powder wasthat of 100 : 54. In round numbers, it may perhaps be nearenough to the truth to say, that the strength of the cylinder pow-der is to that of other powder, as 100 : 60, or 5 : 3. One of theclerks in the laboratory at Woolwich desired a gentleman, in1803, to inform me, (as he suspected I did not know it,) that I