array - space

[MOHAN@USC-ECLC.ARPA]

I am working with images stored as fixnum arrays (with delta =1 i.e. four
pixels packed into a word)  aux as unmarked arrays. (I am on a VAX under
Eunice). How do I deallocate the array-space once I am done with it?
(I use small-segment to allocate space for the array).

Also I would appreciate any pointers of how to speed up programs with 
nested do loops (order of 512x512 x(5 x 5) itterations).

Thanks,

-Rakesh Mohan.
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