466 Prodigious Font of Gunpotuder. 



The barrel being charged with lO grains of powder, its contents when quite full amount- 

 ing to about 28 grains, and the end of the barrel being covered by a circular piece of oiled 

 leather, and the flat fide of the hemifphere being laid down upon this leather, and a heavy 

 cr.nnon, a twenty-four pounder, weigliing 8081 pounds avoirdupois, being placed upon its 

 cafcabcl in a vertical polition upon this hemifphere, in order to confine by its weight the 

 generated elaftic fluid, the heated iron ball was applied to the end of the vent-tube ; and after 

 waiting but a very few moments in anxious expectation of the event. Count Rumford had 

 the fatisfaction of obferving that the experiment had fucccedcd. The report of the explo- 

 fion was extremely feeble, and fo Httlc refembling the ufual report of the explofion of gun- 

 powder, tl-.u the by-ftandcrs could not be perfu;idcd that it was any thing more than a 

 cracking of the barrel, occafioned merely by its being heated by the red-hot ball : yet, as the 

 Count had been tauglit by the refult of former experiments not to expecl any other report, 

 and ai lie found, by putting his hand upon the barrel, that it began to be fenfibly warm, he 

 •was foon convinced that the powder mud have talcen fire ; and after waiting four or five 

 minutes, upon caufing the weight which reftcd upon the hemifphere to be raifed, the con- 

 fined elaftic vapour rudied out of the barrel. Upon removing the barrel and examining it, 

 its bore was found to be choked up by the folid fubftance already dcferibed, and from which 

 it was with fome difficulty that it was freed, and rendered fit for another experiment. The 

 extreme fecblenefs of the report of the explofion, and the fmall degree of force with which 

 the generated elallic fluid ruflied out of the barrel upon removing the weight which had 

 confined it, had infpired the afiiftants with no very favourable idea of tlie importance ot 

 thcie experiments. It was feen indeed from the beginning by their looks, that they thought 

 the precautions to confine fo inconfiderable a quantity of gunpowder as the barrel could 

 contain, perfectly ridiculous ; but the refult of the following experiment tauglit them 

 more refpecl for an agent, of whofe real force they had conceived fo very inadequate aa 

 idea. 



In this fecond experiment, iudead of 10 grains of powder, the former charge, the barrel 

 ■was now quite filled with powder, and the fteel hemifphere, with its oiled leather under it, 

 ■was prefled down upon the end of the barrel by the fame weight as was employed for that 

 purpofe in the firft experiment, namely, a cannon weighing 8c8i pounds. The barrel 

 (which, though fimilar to it in all refpeftj, was not the fame that has already been defcribed) 

 was made of the belt hammered iron, and was of uncommon (Irength. Its length was 2% 

 kiches ; and though its diameter was alfo 24 inches, the diameter of its bore was no more 

 than •* of an inch, or lefs than the diameter of a common goofe quill. The length of its bore 

 •was 2.15 inches. Its diamettr being ii inches, and the diameter of its bore only \ of an inch, 

 the thicknefs of the metal v as \\ inch ; or it was 5 times as thick as the diameter of its bore. 

 The charge of powder was extremely fmall, amounting to but little more than ^'oth of a cu- 

 bic inch ; not fo much ..s would be required to load a fmall pocket piflol, and not one-tenth 

 part of the quantity freq> ^ntly made ufe of for the chaige of a common muficet. Tliis in- 

 confiderable quantity of g'jnpowder, when it was fet on fire by the application of the red-hot 

 ball to 1! e vent- tube, exploded with fuch inconceivable force as to burft the barrel afunder 

 in whici. ''f was confined, notwithftanding its enormous ftrength, and with fuch a loud re- 

 port as to i.irm the whole neighbourhood. The fpeftators turned pale with aflVight and 

 aftoiulhrncut, and it was fome time before ihey could recover themfclvcs. The barrel was 



