British Maritime Postal History Vol.3 - The Union Castle Ocean Post Office, by P Cattell.

Published by Proud-Bailey.  H/B, 153pp.

This third volume in Edward Proud's series on British maritime postal history covers the Union Castle ship mail between South Afica and the UK.  There are chapters on the Ocean Post Offices 1893-1914, the Cape Colony Ocean Post Office 1893-1900, Union-Castle 1900-1910, the Union of South Africa Ocean Post Office, and the United Kingdom and South Africa Sea Post Office.  The postmarks and sailings of the ships are listed, and there is also a valuation guide based on a points system.  Illustrated in black and white, with examples of postcards, letters, and envelopes.