Tom Buck at Hawkeye Biomedical in Atlantic, Iowa, describes a customer:

>>When she uses xylol instead of xylene, she is getting spots on the slide.<<

Xylol is exactly the same thing as xylene (or xylenes). It's an obsolete form 
of the same name. It isn't a xylene substitute.

Bob Richmond
Samurai Pathologist
Knoxville TN