[3] Issel was also renowned at the time for his work on codifying information within anthropology and ethnology, for which he is still remembered.

[4][5] In 1865, he was searching for the presence of Neanderthal man in Malta.

[6] Issel thought that an excavation at the site could prove fruitful.

He dug a trench in the cave’s loose soil and found prehistoric human remains (from approximately 5000 to 4100 BC), and a burnt hippopotamus bone.

[7] Issel participated in several expeditions to East Africa, including one led by Orazio Antinori and Odoardo Beccari in 1870.