Relates history of his edition of Linnaeus' "Systema vegetabilium" produced with [Johann Jacob] Römer [(1763-1819), Swiss physician and botanist] and others, asks Smith to give his blessing to the project and join in the defence against the rival natural systems of [Antoine Laurent de] Jussieu and [Augustin Pyramus] Decandolle. Asks for Smith's advice on the sixth volume, which will include the 'Umbelliferae' and 'Pentandria'.