1880s - W.H.J.Boot - Trees
As far as I can make out William Henry James Boot was well known for three things - in 1883 he published a beautiful book with the title Trees - And how to Paint them in Watercolour. The following year he became Vice-President of the R.S.B.A in 1880 and he was also the first art editor of the Strand Magazine. Whether he ever visited Gibraltar is a moot point - but he did produce several paintings or sketches of the Rock, some of which were used by his magazine.
The Rock from the Western Beach
The Rock from the Calpe Foundry
A series of sketches of Gibraltar including a view of the Rock from Algeciras across the Bay, Rock Gun, the Town looking north, and a view from the Calpe Foundry. The page is probably taken from an 1880s edition of the Strand Magazine