Wet leather

After reading several articles on conservation of leather, and not
having a freeze dry chamber, a set of leather pieces of
archaeological provenience (terrain below the sea level and
therefore permanently wet) were treated by replacing the internal
water with pro analysis acetone:

The treatment started with a month long immersion of the pieces in a
solution of 20% glycerol in water.

A part of the glycerol was supposed to occupy the interstitial
water, softening the leather and conferring more flexibility, and
it's not expected to be removed by the acetone. The pieces were
subjected to 3 consecutive baths of acetone at 1 hour each.

The treatment has not given good results. Some of the leather pieces
are presently very hard and brittle, the development of cracks is
even being observed.

It seems that the process is irreversible. However, should any
"leather dressing" be applied? If yes, what kind?

Some time ago I was asked to help with treating another set of
leather pieces from sub-aquatic maritime provenience, they were
delivered impregnated with a substance that smells like ricinus oil
though it seems altered, as if rancid. On the other hand, it's not
known if any previous desalinization was made.

What would you suggest?

P.S.  It would be preferable to avoid the usage of PEG because the
relative humidity levels in this region are very high and most
institutions do not have appropriate controlled storage. The high
humidity causes this polymer to migrate towards the surface of the
material.

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                  Conservation DistList Instance 12:91
                  Distributed: Wednesday, May 26, 1999
                       Message Id: cdl-12-91-007
                                  ***