greasy specimens

[Kenelm Philip]

	Mark Walker notes that ethyl acetate _vapor_ made specimens greasy.
This is to be expected. Ethyl acetate is a powerful solvent for fats. If
a specimen is immersed in a (relatively) large volume of ethyl acetate, the
fats in the specimen will be extracted and dissolved into the much larger
volume of liquid--thus reducing the amount of fats in and on the specimen.
Ethyl acetate vapor, on the other hand, cannot remove fats from the
specimen.
If any of the vapor condenses on the specimen, the liquid will take up fat.
When the liquid evaporates, a layer of fat will be left on the surface of
the specimen. So the vapor, depending on the amount of condensation present,
will tend to move fats from the inside to the outside of the specimen--not
something one desires.

							Ken Philip
fnkwp at aurora.alaska.edu