De heliometri structura et usu : quibus accesserunt de semita, numero & figura omnium ferme macularum, quae apparuerunt in solis disco a mense Aprili anni 1754 ad mensem Majum anni 1757... ; De altera machinula parallatica ad heliometrum erigendum liber unus...
A 1760 Latin treatise on the heliometer and sunspot observations by Ludovico Zucconi, printed in Venice by Dominico Lovisa for astronomers and scholars. The four vignettes are decorative engraved headpieces built from scrolling acanthus, a shield of checkered tiles, bundled instruments, and open books, drawn in a crisp, dense black-line style a designer could borrow for ornamental borders and cartouches.
