We recently had two documents in the lab exhibiting a noteworthy effect. They were contracts for a violinist’s performance in Lyon dating from the time of the French Revolution, from a Lilly Library collection. Interesting enough, but what really caught my eye was how the ink in selected areas sparkled when turned in the light. Low-power microscopy suggests some type of micaceous material. For me, the question is, was this used as a drying pounce with the bonus of adding some ‘bling’ to one’s signature? Or was the effect alone the chief reason for use? In working with manuscripts for many years, the two other times I’ve seen this were also in French Revolution-era documents. Incidentally, this effect should not be confused with the well-documented and studied crystalline growth one can sometimes see on iron gall ink (whitish or yellowish crystals).
I tried to capture the effect as best as I could by taking multiple exposures with the angle of incident light varying, and then stitching them all together in Photoshop for a rough .gif animation. The effect is restricted to the area associated with the word ‘Bowes’ and the passage of text at the bottom of the view ending with the name “Carpentier”.
There’s a date visible too- 14th of Fructidor, year 13. This references the French Republican Calendar which is itself a fascinating topic. I found a calendar converter online and it looks like this is August 31, 1806, for us Gregorian-minded folks.
p.s. if you want to see a higher resolution animation leave a comment with your email and I’ll send you a file.