Spontaneous Decomposition of a Fabric of Silk . 323 
lion, since the paste is made in eight hours, that formerly 
required four and twenty. 
Every wooden mortar contains twenty pounds of the 
mixture, to which two pounds of water are added gra- 
dually. The paste is first corned : it is then glazed, 
that is, the corns are rounded, by subjecting them to the 
rotatory motion of a barrel, through which an axis 
passes : and lastly, it is dried in the sun, or in a kind of 
stove. 
Experience has shown, that brimstone is not essential 
to the preparation of gunpowder; hut that which is 
made without it falls to powder in the air, and will not 
bear carriage. There is reason to believe, that the brim- 
stone forms a coat on the surface of the powder, and pre- 
vents the charcoal from attracting the moisture of the 
air. 
The goodness of the powder depends on the excel- 
lence of the charcoal ; and there is but one mode of ob- 
taining this in perfection, whieh is distillation in close 
vessels, as practised by the English. 
The charcoal of our pow der manufactories is at pre- 
sent prepared in pots, where the wood receives the imme- 
diate action of the air, which occasions the charcoal to 
undergo a particular alteration. 
Spontaneous Decomposition of a Fabric of Silk.* 
On the night of March 19th, 1802 , during the session 
of Congress at Washington, Jonathan Dayton, one of 
the senators then attending from the state of New- Jer- 
sey, sustained a loss of a pair of black silk stockings in 
an uncommon manner. On undressing himself at bed- 
time, his stockings were the last of his garments which 
he took off. The weather being cold, he wore two pair, 
* Medical Repository, vol. 5. p. 458, 
