Don't you have to also correct for temperature and atmospheric pressure for
altitude for total accuracy?  and use an analytical balance?  I remember a
post doc doing this years ago (pre-automated pipettors) and should have
taken notes.  
Gayle Callis
MT,HT,HTL(ASCP)
Histopathology Supervisor
Veterinary Molecular Biology
Montana State University - Bozeman
Bozeman MT 59717-3610

406 994-6367
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