139 
the Swedish Stone Paper. 
mens prepared with sulphat of iron were considerably 
swelled* but those made without linseed oil seemed to 
have scarcely swelled at all. Those* however* which I 
had daubed over with boiled linseed oil* or linseed oil 
varnish* exhibited as little appearance of change as the 
Swedish. 
I put a square inch of each of the different kinds upon 
an iron spatula* together with a like quantity of beech 
wood* and exposed the whole to a strong heat in the 
mouth of a furnace. After fifteen minutes the wood be- 
gan to burn* and in fifteen minutes more was reduced to 
ashes. The fragments of the different specimens of the 
stone paper* exposed to the same heat* were in such a 
state* of ignition that they hissed when immersed iirwa- 
ter. I* however* examined them with great attention* 
The fragment of the Swedish manufacture was some- 
what black on the surface* and puffed up into small blis- 
ters ; but did not seem to have burnt* or to have changed 
its form. The specimens prepared with the sulphat* be* 
ing more spongy at the edges* burnt; but so slowly* that 
in those of the worst quality the fourth part was scarcely 
consumed in the above time. All the rest* inferior 
in nothing to the Swedish specimen* resisted the fire 
with equal strength ; so that most of them were only 
a little blackish on the surface* and entirely free from 
blisters ; nor did there appear any difference that could 
be ascribed to the glue or linseed oil employed* as they 
were all of the same consistence* and none of them seem- 
ed to have been warped by the heat. 
I then put some of the same fragments toasted in the 
fire on a red hot plate of iron* and immediately exposed 
them for fifteen minutes to a strong heat in the middle of 
a furnace. The Swedish specimen burnt* and for five 
minutes emitted a thick smoke ; then appeared of a white 
heat for some time* and dA the end of fifteen minutes was 
