Godman began collecting moss when he was a sickly child. It was a popular Victorian pastime which the naturalist pursued throughout his life, meaning that the albums represent some of his earliest encounters with the natural world and his ensuing 50 years of gathering moss.
The albums were first sold in the late 1980s before passing into the book trade.
Jeremy Knight, curator of the museum in West Sussex, came across them during the August PBFA Online Book Fair.
The £880 acquisition was made with the help of the Friends of Horsham Museum, a close descendant of the Godman family and the dealer.
The albums includes all varieties of British moss, offering researchers a look at changing habitats in the UK.
Godman, a Horsham resident, had many and varied collecting interests. On his death his huge assemblage of Islamic pottery was gifted to the British Museum, while his collection of ornithology went to the Natural History Museum in London. The album will be included in an exhibition on Godman’s life set for next year when Horsham Museum reopens.