Claim: German born Ferdinand Ludwig Herff was a physician who hung out with Alexander von Humboldt, a geographer from Prussia, graduated in 1843 and became a surgeon.
Evidence: Ferdinand Ludwig Herff (1820–1912) was a 19th-century German-born physician who emigrated to Texas and became a medical pioneer in San Antonio. The family social circle included naturalist Alexander von Humboldt and Prince Albert of Saxe-Coburg and Gotha. Friedrich Wilhelm Heinrich Alexander von Humboldt (14 September 1769 – 6 May 1859) was a Prussian polymath, geographer, naturalist, explorer, and proponent of Romantic philosophy and science. Herff completed his medical education at the University of Giessen in 1843. Upon graduation, he served a surgical internship with the army of Hesse, and learned techniques in plastic surgery and the treatment of tuberculosis.