The Question of the Powders

           Thereremainedforconsiderationmerelythequestionofpowders.Thepublicawaitedwithinterestitsfinaldecision.Thesizeoftheprojectile,thelengthofthecannonbeingsettled,whatwouldbethequantityofpowdernecessarytoproduceimpulsion?

           ItisgenerallyassertedthatgunpowderwasinventedinthefourteenthcenturybythemonkSchwartz,whopaidforhisgranddiscoverywithhislife.Itis,however,prettywellprovedthatthisstoryoughttoberankedamongthelegendsofthemiddleages.Gunpowderwasnotinventedbyanyone;itwasthelinealsuccessoroftheGreekfire,which,likeitself,wascomposedofsulfurandsaltpeter.Fewpersonsareacquaintedwiththemechanicalpowerofgunpowder.Nowthisispreciselywhatisnecessarytobeunderstoodinordertocomprehendtheimportanceofthequestionsubmittedtothecommittee.

           Alitreofgunpowderweighsabouttwopounds;duringcombustionitproduces400litresofgas.Thisgas,onbeingliberatedandacteduponbytemperatureraisedto2,400degrees,occupiesaspaceof4,000litres:consequentlythevolumeofpowderistothevolumeofgasproducedbyitscombustionas1to4,000.Onemayjudge,therefore,ofthetremendouspressureonthisgaswhencompressedwithinaspace4,000timestooconfined.Allthiswas,ofcourse,wellknowntothemembersofthecommitteewhentheymetonthefollowingevening.

           ThefirstspeakeronthisoccasionwasMajorElphinstone,whohadbeenthedirectorofthegunpowderfactoriesduringthewar.