Real Deal Spolas

[Feinman]

Thanks Ivor, that sounds right!  I think the vitriol might be referring to alum. My plan is to make a size solution of hide glue with a bit of alum; I am going to mix titanium dioxide and a bit of powdered marble into it to create a paste, which I will sponge into the surface. This should keep things flexible and strengthen them a bit while whitening the leather.  When dry, I plan on a final coat of a drying oil (safflower probably) with beeswax and a bit more titanium white.  This should almost waterproof the whole, and seal it, while the basic properties of the white sizing should counteract any damaging acids from the drying oil finishing coat.  I have sealed a lot of leather with the beeswax / oil; it's also an oil painting medium, and very flexible.