The Arrowsmith River was named by explorer George Grey crossed it on 11 April 1839, on his second expedition along the west coast. He named it after the distinguished English cartographer John Arrowsmith.

The river commences just south of Arrino and north-west of Three Springs near the Midlands Road and flows in a westerly direction for  85 kilometres,  terminating in Arrowsmith Lake, 9 kilometres inland from Cliff Head.

John Arrowsmith (1790–1873) joined his uncle in the cartography business in 1810. In 1830 Arrowsmith and his two cousins, who were also part of the business, formed the Geographical Society of London, later to become the Royal Geographical Society.

Arrowsmith produced the maps for the published journals of Grey’s two Western Australian expeditions. In 1863 he received the gold medal of the Royal Geographical Society.

 

References:

https://en.wikipedia.org/wiki/John_Arrowsmith_(cartographer)