Isles of Scilly 1803

Historical Background

William Heather’s New and Improved Chart of the Isles of Scilly, dated 1803, was drawn from what its title calls “the most approved surveys”. The sheet concentrates on the islands and their immediate waters, giving rocks, passages and depths much of the attention that a land map would give to roads and towns.

Map Details

• Original title: Heather’s New and Improved Chart of the Isles of Scilly, Drawn from the Most Approved Surveys
• Chartmaker and publisher: William Heather
• Published: London, 1803
• Area shown: The Isles of Scilly and surrounding rocks, channels and anchorages
• Approximate original scale: 1:24,300, as catalogued by the Boston Public Library
• Catalogued original dimensions: 62 × 76 cm; these are not the dimensions of the reproduction print
• Visible features: Depth soundings, navigational lines, Broad Sound, St. Martin’s Flats, island outlines and an oval title panel

A Chart of the Water Between the Islands

St. Mary’s occupies the eastern side of the central island group, with St. Martin’s above it and St. Agnes to the south-west. Tresco and the neighbouring islands form a closely packed cluster farther north. The spaces between them are densely annotated: for a mariner, these stretches of water were as important as the land.

Broad Sound is clearly named across the middle of the chart, while St. Martin’s Flats appears farther north-east. The contrast between broad passages, shallow ground and scattered rocks explains why the archipelago required a detailed chart of its own.

Soundings and Courses

Small depth figures extend well beyond the islands into their approaches. Together with the marked hazards and anchoring areas, they record information that could help a crew judge where a vessel might pass and where extra caution was needed.

Lines radiate from several centres across the sheet. Their repeated intersections are part of the chart’s navigational framework, allowing bearings and courses to be considered across the surrounding sea. The result is a markedly different visual pattern from the roads and boundaries of a conventional county map.

Heather’s Maritime Map Trade

The large oval title panel balances the detailed island group. Its wording advertises an improved chart compiled from existing surveys, placing the sheet within the practical London trade in navigation charts at the beginning of the nineteenth century.

Read today, the engraving preserves the islands as a working seascape: named channels, isolated hazards, measured depths and familiar island shapes share the same sheet. These details give the reproduction its interest both as a maritime document and as a fine art print.