MISCELLANEA. 
69 
semi-decomposed animal membrane. Even after being washed^ 
it preserves an odour of fish or sea-water. This substance is 
every wbere filled with large bubbles of air, sometimes of several 
inches in breadth, which are so tightly enclosed in the substance 
that they cannot escape therefrom of themselves, but ascend to 
the surface in great number, as soon as the slimy surface is 
torn by means of a stick. The quantity of air thus enclosed is 
so considerable, that hundreds of bottles might be filled with it. 
If a burning chip be brought into this air, it inflames, and burns 
with a bright flame. The air consists of 51 per cent, of oxygen 
gas, and 49 per cent, of azote. Wohler is of opinion, that at 
first pure oxygen is evolved, which, however, like air in an animal 
bladder, is partly exchanged for atmospheric air. It must be 
observed, that the salt water, when recently pumped out, con- 
tains such a quantity of sulphuretted hydrogen, that it might be 
taken for sulphuretted water : having, however, once passed 
through the thorn walls, or filters, into the salt basins, it en- 
tirely loses its odour. It was ascertained by microscopic obser- 
vation, that the membranous mass consisted of living and moving 
infusoria — species of Navicula and Galionella being interwoven 
with extremely delicate and colourless threads of confervae. 
Since, according to the supposition of Ehrenberg, Priestleyan 
green matter is not a vegetable substance, but consists of real 
animalculse, especially Chlamidomonas Pulvisculus, and Englenae 
viridis, which likewise exhale 60 per cent, of oxygen, the evolu- 
tion of the before-mentioned gas cannot be ascribed to the con- 
fervse existing in the mass, but rather to the infusoria, and to 
these latter alone. — F. Wohler, Poggendorfs Annalen. 
To separate Silver or Gold from Lead. — Take a few grains of 
bone ash, make it into a paste with a little saliva, spread it about 
one line thick on a piece of charcoal, and make a shallow im- 
pression in it, to receive the globule of metal. Expose it to the 
heat of the blow-pipe, so as to burn it white and hard, and then 
melt the globule of the alloy on it, and keep it in a constant red 
