On Tue, 29 May 2001, Anthony f. Brandwood wrote:

> > Fragmentation of paraffin-embedded tissue when floated on a
> > warm water bath is _not_ one of the faults of formaldehyde or
> > any other fixative. Your problem has to be the fault of the
> > contract lab that collects money for not dehydrating, clearing,
> > infiltrating and properly blocking out your specimens.
> 
> We have also had this problem occuring from time to time ... 
> ... The blocks had not been jammed tight in the basket 
> during processing and all the solvents had been reasonably fresh and the 
> processing schedule been used for many years to process CNS tissue without 
> many problems. Any Suggestions?

Only that the tight jamming might have impeded penetration
of solvents & wax into some of the specimens - but you must
have thought of that one.
----------------------------------------
John A. Kiernan
Department of Anatomy & Cell Biology
The University of Western Ontario
London,  Canada   N6A 5C1
   kiernan@uwo.ca
   http://publish.uwo.ca/~jkiernan