Recherches expérimentales sur la cause des changemens de couleurs dans les corps opaques et naturellement colorés
An 18th-century French scientific treatise on the causes of colour change in opaque bodies, written by the English-born Edward Hussey Delaval and printed in Paris in 1778 for a learned readership. Its four pictures are typographic ornaments: a black-line floral cartouche with scrolls, a rectangular scrolled panel with a central shell motif, a sprig of flowers and berries, and a faint heraldic crest with a crown and wreath. A designer could draw on their rococo scrollwork, botanical sprays and crest framing for borders and vignettes.
