92 LETTEES OF BEBZELIUS 



neighbourhood which is now under construction ; all 

 gave most satisfactory results, and in the opinion of 

 the engineers present proved that for blasting purposes 

 guncotton is preferable to gunpowder. One part of 

 guncotton is under these circumstances as effective as 

 five parts of powder. In many instances the gun- 

 cotton produced eight and ten times as great an 

 effect as powder. Although I experimented almost 

 daily for many months I have never had the slightest 

 accident and not once has any of the cannons, mortars 

 or small guns from which many hundreds of shots 

 have been fired under my direction, exploded. As far 

 as my own observations go I have not even observed 

 that the firearms were perceptibly damaged by the 

 guncotton. I once caused forty shots in succession 

 to be fired from an American carbine, and after the 

 experiment it was as clean as before. I find it con- 

 venient to saturate my guncotton with a solution of 

 potassium nitrate, for experience shows that guncotton 

 so treated is more readily compressible, without 

 becoming perceptibly harder to explode. Possibly 

 this film of potassium nitrate enveloping the explosive 

 filament makes it less easy to explode and more 

 uniform in action. In England they are now making 

 arrangements to prepare guncotton on a large scale, 

 and I think that there it will soon be widely used for 

 blasting. I and others also have not yet given up 

 the hope that guncotton will likewise be applicable 

 for purposes of war. It is anything but honest of 

 the French to continue to claim priority in the 

 discovery of guncotton on account of Bracconnot's 



