[1] Mayer retired from business in 1873, and died unmarried at Pennant House, Bebington, Cheshire, on 19 January 1886, aged 82.

In 1861 Mayer was deceived into purchasing some spurious papyri of the Gospel of Matthew and other scriptures, concocted by the forger Constantine Simonides, who also induced him to publish them.

For this collection Mayer printed in 1856 a catalogue and history, compiled for him by Charles Roach Smith, entitled Inventorium Sepulchrale.

[3] A number of books were printed wholly or in part at Mayer's expense, among them being:[3] He assisted largely in the publication of Benjamin Thorpe's Diplomatarium Anglicum Ævi Saxonici, 1865, and he supplied Eliza Meteyard with most of the materials for her Life of Wedgwood and Group of Englishmen.

He contributed the following among other papers to its Transactions:[3] In 1876, he printed a volume on Early Exhibitions of Art in Liverpool, with some Notes for a Memoir of George Stubbs.

He had previously disposed of a collection of objects of art relating to the Bonaparte family, but at the death of the owner (Mr. Mather) it was bequeathed to the corporation.

Another portrait as a young man, painted by William Daniels, was in the Mayer Museum, Liverpool; it is now in the Walker Art Gallery.