Humboldt talked and talked, Gallatin noted, ‘twice as fast as anybody I know’. Humboldt spoke English with a German accent but also German, French and Spanish, ‘mixing them together in rapid Speech’. He was a ‘fountain of knowledge which flows in copious streams’. They learned more from him in two hours than they would from reading books for two years. Humboldt was a ‘very extraordinary man’, Gallatin told his wife. Jefferson agreed – Humboldt was ‘the most scientific man of his age’.

