Bay of Biscay

Late 19th century admiralty chart of the Bay of Biscay off France’s western coast.

This wonderful admiralty chart covers the western coast of France and northern Spain along the Bay of Biscay in the northern Atlantic Ocean. Though some interior detail is provided through place names, transportation routes, and hachure topography, the real emphasis is on the sea and coast.

Depth soundings, in fathoms, are listed throughout the image and often accompanied by a small letter indicating the composition of the seafloor (an important consideration when dropping anchor). Navigational hazards like shoals and reefs are also given due attention.

Three compasses assist in the calculation of lines of magnetic delineation, and a cautionary note in the lower left reminds sailors of the local currents and often misty conditions. Lighthouses are individually highlighted by hand and include the height and visibility. Some of dubious purport are noted as ‘not to be depended upon.’

The chart was published in London in 1888 by the United Kingdom Hydrographic Office under the direction of Captain William James Lloyd Wharton, Hydrographer of the Navy. Engraved by Davies & Company.