Frank wrote several sections of questions and answers in his book. I'll just give the answers..
Remember, this was 1950 so some of the materials are not around anymore!Three Different Mixtures for adhering Smalts:
1. For a job carrying a heavy inscription use dry lamp black ground in half and half raw linseed oil and oustide spar varnish, adding one-fourth its bulk in keg white lead; reduce to pencilling or brushing consistency which retards drying so that smalt will adhere.
2. Lamp black ground stiff in boilded linseed oil with a trifle of finishing varnish and past white lead added.
3: Same as above subsituting rubbing varnishe for finishing varnish for average fascia board carrying one or two lines of lettering.
To Improve Lettering Mixtures, add a trifle of varnish. It speeds up any lettering mixture assuring perfect rapid easy control of stroke and maintains the always desired spring in the lettering brush.
Adding Prussian Blue to Black Lettering for Window and Board Work:
Prussian blue added to lamp black enriches it and kills its gray cast.
To Retard Japan Gold Size, add some finishing varnish or fat oil.
Emergency Sizes for Surface Gilding: Japan gold size, rubbing varnish, finishing varnish, spar varnish, fat oil.
Order of Drying Qualities of Following Liquids (with slowest dryer first and fastest last)
Fat linseed oil, raw linseed oil, wearing body varnish, boiled oil, Japan rubbing varnish, gold size, shellac