[1] However, various sources cite two younger brothers: Holt Waring Archer and Richard Henry Verling (H.V.)

Archer’s great-uncle on his maternal side, the Reverend Holt Waring, was the Dean of Dromore.

[4] Archer moved to Dublin around 1849, where he helped found the Dublin Microscopical Society and became involved in pursuits of scientific study and librarianship which would define his life and career, spending "his early life…unselfishly devoted to scientific research by which he secured a widespread reputation little understood beyond the abstract world of science.

"[1] After his move to Dublin around 1849, Archer pursued a career in business, but quickly made a name for himself as a talented naturalist in his leisure time.

[6] Despite these achievements, Archer's humble and shy character seemingly led him to decline opportunities like a professorship of botany at the Royal College of Science for Ireland.

[3] Archer subsequently made a career change when he became the librarian of the Royal Dublin Society in 1877.

Luckily for Archer, the Council of Trustees decided to appoint him as the first librarian of the NLI in February 1878.

[7] Setting himself to his task with zeal, Archer quickly gained a positive reputation among librarians for his dedication and work ethic.

Archer likewise strongly influenced the internal design of the new library building, inspiring Dublin-based architects, Deane & Son, with his 1881 pamphlet: "Suggestions as to public library buildings: their internal plan and construction, best adapted to effect economy of space.

"[8] Archer retired from his post in 1895 due to poor health, but his establishment of relatively novel systems like the Dewey Decimal Classification, as well as a dictionary catalogue had a lasting positive impact for library users.

Archer was said to believe that, "All the machinery and the clever devices of librarians have one important end — to serve the reader, to place rapidly before every student, sooner or later, the source of information which he needs.