Constantly reminded of Smith by his "very assiduous & ever-to-be-encouraged correspondent Mr G[eorge] Don". Made to doubt his own knowledge after seeing Don's "acute observations", and wonder "where have all these things lain since the days of Adam, that no one should have noticed them before". Does not wish for Smith to be charged for any of [the Don letters and plant specimens]. Eagerly awaiting confirmation of Smith's visit.