Notes upon indigo
A chemical and botanical treatise on indigo by John Lord Hayes, printed in Boston in 1873 and aimed at dyers and scientific readers. Its two pictures are plain black-and-white wood engravings of indigo plants, one a tall flowering stem with spreading leaves and the other a branch of pinnate leaves with clustered flower spikes. A designer could draw on their crisp, hatched line work for botanical plates, vintage seed packets, or textile pattern motifs.
