HG Porter was one of the fathers of Nigerian philately, collecting, researching and publishing between the 1920s and the late 1950s. His collections were dispersed in the 1950s, surfacing most commonly nowadays in 'Porter covers' sent to and from postmasters in small postal agencies. From the 1940s onwards Porter was building up information and resources for a major publication on Nigerian philately which never saw the light of day. The whereabouts of much of this material is unknown, but some notes have turned up in the RPSL's archive of documents bequeathed by John Sacher, and was copied by Ray Harris. Some of this material has been published elsewhere, much has not.

1. Lagos postal history introduction - a mix of general history of Lagos colony, with photographs (rather grainy), information about postal services, and some illustrations of auction material. 9 pages 
2. Lagos - the stamps. 25 pages covering the issued stamps, designs, printing details, colours, forgeries etc.
3. Lagos - the postmarks. 12 pages of drawings and notes, including postal stationery
4. Northern Nigeria Posts and stamps. 32 page typed manuscript, covering history, postal serviuces stamps (with design and printing details), and postmarks 
5. Northern Nigeria Posts and stamps version 2 16 pages covering similar ground, though with photographs, and omitting descriptions of cancellations 
6. Northern Nigeria - the postmarks 8 pages of illustrated notes 
7. 1894 Calabar provisionals 8 pages of notes including an image of an entire row of the surcharge doubled rarity
8. Southern Nigeria posts and postmarks 13 pages of notes, illustrated, including a drawing of the old Balogun St GPO premises