294 Chemical Preparations. 
ploding heat as may be. Having dried it, burn a few grains upon 
paper, when the explosion will be found equal to that of detonating 
silver. ‘The paper will be shivered to pieces, and the coal of fire 
annihilated, of the powder be well dried. 
I think the powder burns with most violence taken after the alkali 
has acted on the fulminating mercury two days, but a great change 
is effected upon the composition in a little time. Examine the con- 
tents of the glass on the fourth day, and the fulminating mercury 
will be found subsiding ; the peculiar action, by which its stiffness 
was created and kept up, having gone by, and the detonating quali- 
ties of the powder being lost. If the composition be now pressed and 
dried, it will explode very mildly, and without flame, or at least with- 
out appearance of flame in a light room. 
I poured a saturated solution of caustic potash into one ounce of dry 
fulminating mercury, and the next day I pressed it as dry as I con- 
veniently could, and laid it aside for half an hour, when it exploded 
spontaneously. I observed when I took it out of the press that it 
had become hot, but thought no more of it until it exploded. 
Into a ladle of boiling solution of caustic potash I stirred a quanti- 
ty of fulminating mercury, and then poured the mixture upon @ filter: 
on cautiously pressing the filter, the composition took fire whilst it 
was yet as thin as paste. 
I think the powder cannot be dried so as to preserve its detona- 
ting qualities. The potash, though retarded in its operation, never 
theless continues it, and in a few days fulminate of potash is genera- 
ted. I prepared a quantity of these crystals to send you, but they have 
deliquesced, and I have not inclosed them. ‘These are NOT “true 
fulminates,” having no fulminating disposition ; and the term can be 
true only as applied to the triple compound, whilst a peculiar action 
is going on between the fulminite of mercury and the potash, s0 fat 
as caustic potash is concerned. Lime water, carbonate of potas’s 
carbonate of soda, and ammonia, all blacken fulminating mercury, 
and generally improve the explosive qualities in the first instance, but 
injure or ruin the preparation soon after. Solution of chloride of lime 
has no action upon fulminating mercury ; iodine gives the mass 4 Vel" 
million color, and spoils its fulminating qualities. 
The exploding point of fulminating mercury an 
varied by the concentration of the caustic potash. 
diluted to various degrees of strength, there will be correspon 
points of temperature at which the product will be ignited. 
will likewise be corresponding powers of detonation. 
