1870 Imray Chart of the Gulf of Siam (Thailand)

A large-format, intricately detailed blueback nautical map of the Gulf of Siam and nearby waters produced in 1870 by James Imray and Son, part of their 'East India Archipelago - Western Route to China' series. It was used for actual navigation and there are pencil marks and manuscript updates associated with maritime use.

A Closer Look

Coverage ranges from the Malay Peninsula opposite the Anambas Islands, up through the Gulf of Siam, down the coast of Thailand and Cambodia, and to the Mekong Delta, in today's southern Vietnam. Currents, shoals, reefs, hazards, anchorages, beacons, magnetic variations, the best routes to and from Hong Kong, and other maritime features are recorded. Helpful notes are provided, such as information relating to tides and the location of the U.S. Consulate outside Bangkok. Six insets appear, with a large inset of the Gulf of Bangkok predominating at top-right, and additional insets of the Chanthabun or Chanthaburi River, the Chao Praya River ('River Bangkok'), the Mekong Delta near Saigon, the Hon Khoai archipelago (here as Pulo Obi), and Côn Sơn Island (Pulo Condore) are included. Three stretches of coastline are illustrated in profile.

Blueback Charts

Blueback nautical charts began appearing in London in the late 18th century. Bluebacks, as they came to be called, were privately published large format nautical charts known for their distinctive blue paper backing. The backing, a commonly available blue manila paper traditionally used by publishers to wrap unbound pamphlets, was adopted as a practical way to reinforce the low-quality paper used by private chart publishers in an effort to cut costs. That being said, not all blueback charts are literally backed with blue paper. The earliest known blueback charts include a 1760 chart issued by Mount and Page, and a 1787 chart issued by Robert Sayer.

The tradition took off in the early 19th century, when British publishers like John Hamilton Moore, Robert Blachford, James Imray, William Heather, John William Norie, Charles Wilson, David Steel, R. H. Laurie, and John Hobbs, among others, rose to dominate the chart trade. Bluebacks became so popular that the convention was embraced by chartmakers outside of England, including Americans Edmund March Blunt and George Eldridge, as well as Scandinavian, French, German, Russian, and Spanish chartmakers. Blueback charts remained popular until the late 19th century, when government subsidized organizations like the British Admiralty Hydrographic Office and the United States Coast Survey began issuing their own superior charts on high quality paper that did not require reinforcement.

Imray's 'East India Archipelago' Series

This chart was part of series of nine maps issued by Imray entitled 'East India Archipelago' (subtitled 'Western Route to China') covering from the East Indies to the central China coast. Imray's charts are notable for their detail and their availability to traders and other mariners, as opposed to the charts of the Admiralty, which were primarily intended for government and military use. Imray nevertheless drew on Admiralty charts, while also incorporating information directly from mariners (each chart requests communication for improvements to future editions). Thus, his were typically the most detailed and up-to-date charts available on the private market.

This series of charts was particularly important for traders bound for Hong Kong, Shanghai, or other 'treaty ports' in China. A thorough understanding of currents, trade winds, coastal hazards, and other factors was absolutely necessary for increasing the likelihood of a safe journey to and from China. Even the adoption of steam powered ships did not fully overcome these obstacles, while adding new ones, such as the need to stop at coaling stations.

Publication History and Census

This first edition chart was produced by James Imray and Son in 1870. We are aware of later editions from 1882, 1886, 1888, and 1900. Regardless of edition, the only known institutional holding of this chart is with the National Library of Australia, an example of the 1882 edition.