“…I have been accused of having acted, if not an unfair, at least an ungenerous part, by trespassing upon ground, which I knew to be, by right of pre-occupancy, his [Smith]. I certainly did know, as early as the year 1804, that such a map was begun; but I appeal to all the friends of Mr Smith, with whom I have conversed upon the subject, and especially to the individual who complains of my conduct, whether he, and they did not, for a long time afterwards, in consequence of a variety of circumstances which it is unnecessary to detail, consider its completion, and still more its publication, hopeless. In the belief that the work had been virtually abandoned by Smith, it was undertaken by me.…Mr Smith’s map was not seen by me till after its publication, and the use I have since made of it has been very limited. The two maps agree in many respects, not because the one has been copied from the other, but because both are correct.…” [from Greenough, G B, ‘Memoir of a Geological Map of England: to Which are Added, an Alphabetical Index to the Hills, and a List of the Hills Arranged According to Counties’ (1820), p4.]
George Bellas Greenough's 'A Geological Map of England and Wales', 1820. The Geological Society. 2018年2月17日閲覧。