I have only just found your message. Your great uncle is related to our family by his marriage to Beatrice Ainslie. I have a photo of their marriage in Singapore, I believe. He was a teacher and musician. I have some of his music. My mother, Joanna Cross, remembers him. She was child when he was married to Bea. They all lived in Bangkok. Beatrice went to England in the 1930s and visited two of his sisters in Bognor Regis. She studied at a secretarial school and I believe I have a photo somewhere. Bea was the eldest sister of three; my grandmother was Connie and her youngest sister was Jean. I am writing a book about Connie and have a website about her www.conniemangskau.com
There are photos on the website but none of A.G. Beaumont. I am happy to give you whatever information I have about him.