Participated in an English expedition to Sierra Leone in west Africa (1792-94). He became however plundered on all collections and belongings but succeeded with help from his friends that once again visit Sierra Leone and do a new collection which was completed 1796.
Left documentation
Dairynotes are preserved on Uppsala university library, Sierra Leone Journals 1795-96.
Noterbart
His extensive collections is today scattered on several museums in Europe.
He was senior lecturer in oriental languages. He was appointed 1812 to e. o. professor in matter medica.