ON THE CHEMICAL PROPERTIES OF SILK. 155 
air in the upper part of the globe, which, when 
examined by the established test, appeared to be 
very pure. In three days he collected three and 
three quarters of a cubic inch of pure air, into which 
a wax taper being introduced, that had just before 
heen blown out, the wick only remaining red, it 
instantly took fire, and burned with a bright and 
large flame. The water in the globe had acquired 
the smell of raw silk ; it lost something of its trans- 
parency, and assumed a faint greenish cast. 
It was observed, that when this experiment was 
made in the dark, only a few inconsiderable bubbles 
were formed, which remained attached to the silk; 
nor was it otherwise when the glass globe was re- 
moved into a German stove. In the latter case, 
indeed, some single bubbles had detached themselves 
from the silk, and ascended to the top, but the air 
was in too small a quantity to be either measured 
or proved. 
Dr Lardner says, “‘ The imperishable nature of 
silk, even under circumstances peculiarly unfayour- 
able to the preservation of animal substances, forms 
another of its qualities which is deserving of re- 
mark. Some years ago, the sexton of the parish of 
Falkirk, in Stirlingshire, upon opening a grave in 
the churchyard, found a riband about the bone of 
an arm, and which, being washed, was found to be 
entire, and to have suffered no injury, although it 
