Observations on certain horny excrescences of the human body / On nebulous stars properly so called. In Philosophical Transactions 81 (1791)

Herschel, William (1738-1822). On nebulous stars, properly so called. In Philosophical Transactions of the Royal Society of London 81, part 1 (1791): 71-88. With: Home, Everard (1756-1832). Observations on certain horny excrescences of the human body. In ibid.: 95-105. Whole volume, 4to. vi, [2], 127, [1], 26, iv, 129-438, [2, incl. errata]pp. 10 engraved plates. 275 x 215 mm. Calf gilt ca. 1791, spine rubbed, hinges cracked, corners worn. Very good, clean copy. Engraved bookplate of John Douglas, Bishop of Salisbury (1721-1807).

First Editions, journal issues. Herschel's paper records his observation in 1790 of the planetary nebula now known as NGC 1514, which caused him to reconsider his hypothesis that all nebulae were in fact star clusters disguised by distance. NGC 1514 "is so close to Earth that William was able to see the central star that in fact is always present in a planetary nebula. Accordingly, William classified the object as a nebulous star. Marveling at what he saw, he accepted the evidence before his very eyes, even though it contradicted the theory he had argued . . . He had to accept that the spherical glow around the star could not be a distant globular cluster that by pure chance lay in exactly the same direction as the star: it must be ‘true nebulosity' out of which the star was condensing" (M. Hoskin, William and Caroline Herschel: Pioneers in Late 18th-Century Astronomy, pp. 40-41).

Home's paper contains the original description of cornu cutaneum, a dermatological condition that produces unusual keratinous skin tumors with the appearance of horns. Garrison-Morton.com 4017.