The Blavatsky Archives website has images of a copy of The Secret Doctrine inscribed to Bertram Keightley, another of the editors of the book. It can be seen here. Bertram (1860-1944) was the uncle of Archibald Keightley (1859-1930), though he was actually a year older (Bertram’s brother was the father of Archibald Keightley). The biographical entry on him in Blavatsky Collected Writings, vol. 9, p. 435, gives the year of his death as 1945, but the correct date of his passing is October 31, 1944.
Bert and Arch, as they were known, came in contact with HPB during her 1884 visit to London and remained dedicated theosophists for the rest of their lives, becoming key players in later theosophical history. Archibald Keightley died New York City, while Bertram Keightley died in Allahabad, India. They are remembered by Mohandas Gandhi as playing an important role in his rediscovery of his Indian heritage.
One of our readers has alerted us to a collection of books by Blavatsky that will be put up for sale on Ebay in June. These include early editions of Isis Unveiled, The Key to Theosophy, the Voice of the Silence, and an 1888 two-volume set of The Secret Doctrine. The list can be accessed here.