Some futher comments on image quality and the purposeful destruction of
historical materials.

We are currently able to view on microfilm, on the internet, and on
cd-rom, images
of the 1790 census. Of these, the cd-rom is a derivative of the
microfilm, and the internet version is a derivative of the cd-rom.

These images are available in black and white only.
The images vary in quality according to:
1. the original exposure of the original negative and the exposure of
any derivatives.
       the ability to re-capture extra data depends on
       (a) access to the original negative or
       (b) access to the original material.
2. the quality of the ink used to record the original data.
        (a) in some cases the ink has faded, as the ink ingredients varied from
place to place.
            1. re-photographing the original in color may restore some
of the lost data.
            2. re-photographing the original using ultra-violet light
may restore data
                        otherwise invisible.
            3. re-photograhing the original using infra-red film may
restore data
                        otherwise invisible.
3. the resolution of the original image.
4. the size of the original image.

My preference would be for a clear, unequivocal, easily reproducible
image in color.  This is not now possible if we were only able to obtain
access to the original microfilm copy or its derivatives. While we are
able to obtain partial data from the existing black and white
derivatives of the original, the copies we are currently able to obtain
quite demonstrably do not equal the original.

It would be, in my less than humble opinion, a tragedy to destroy the
underlying original on the rather specious grounds that the copies we
have are sufficient or that we do not have sufficient space to store
them. I'm reasonably confident that no argument for the destruction of
historical materials is persuasive on its face, and certainly would not
withstand the presentation of reasonable alternatives.

Here's an offer for those of you who would discard historical materials,
whether books or other paper. I will travel to your place of business,
and retrieve and store such materials at my own expense.  If you must
dispose of them, give them to me, and I will preserve them.

Fire, flood, war and stupidity are the natural enemies of historical
preservation.  Sometimes these forces combine in such a manner that what
we once thought safely preserved is now lost forever.  Why accellerate
process of destruction?   Who benefits from destruction?

Tom Perrin
East Windsor, NJ