[ 343 ] 



LXVII. Remarks on Mr. Sturgeon's Paper " On the Inflam- 

 mation of Gunpowder by Electricity." ByMv.Tnos. Howldy. 



To the Editors of the Philosophical Magazine and Annals. 

 Gentlemen, 



IN consequence of some passages in Mr. Sturgeon's paper, 

 inserted in your Number for January, appearing to me to 

 insinuate that my experiments on the inflammation of gun- 

 powder were not actually performed in the manner which I 

 stated, but that I concealed, either designedly or ignorandy, 

 some esse7itial particular which rendered them successful, I 

 feel the necessity of requesting the favour of your inserting 

 my present letter. Mr. Sturgeon introduces the subject of 

 my experiments with the following observation. " The most 

 extraordinary method of effecting the ignition of gunpowder 

 by the electric fluid, that I have yet heard of, is that stated 

 by Mr. Howldy, in the Philosophical Magazine, vol. Ixviii. 

 p. 173." This is a strong, though an indirect, testimony that 

 my method is at least original. He then proceeds : " I have 

 been induced," says Mr. S. " to pay some attention to this 

 method."—" I think, however, it is to be regretted that Mr. 

 Howldy has not mentioned the hygrometrical state of that 

 part of the table (' four inches') between the extremity of the 

 chain and the outside of the jar : as it is possible that a varia- 

 tion in that particular may vary the result of the experiment." 

 Now, I can relieve Mr. Sturgeon's regret, by assuring him that 

 the part of the table which he has mentioned and suspected, 

 was perfectly dry, and free from moisture of every kind, as 

 was likewise every other part of the table, and the apparatus 

 employed, when the experiments in question were made. The 

 table is of elm ; it was made and has been employed solely 

 for the purpose of supporting electrical and other apparatus. 

 Mr. S. next remarks, " Considering, however, that four inches 

 is a long striking distance through dry air, — " It would indeed 

 have been a long striking distance, under the circumstances 

 I have described, supposing the charge to have actually struck 

 or passed over that distance in the form of a spark. But the 

 distance or interval was made long, expressly for the purpose 

 that the charge might not strike over it ; for if the charge had 

 struck over that interval, the experiment would not have been 

 successful. For in any arrangement that is made according 

 to my method, when the jar is discharged, whether the inter- 

 val between it and the chain be four, three, or two niches, the 

 only appearance in that interval is a litde light at and near 

 to the extremity of the chain; from which place the charge 



becomes 



