Phosphate cargoes

This week we will have a look at wrecks from one of our most picturesquely-named departure points, revealing Britain’s connections with Sombrero or Hat Island in Anguilla, and taking a look at a typical 19th century cargo whose true nature is often hidden behind agrochemical euphemism – nitrates, phosphates, fertilizer.

The island once looked like a three-dimensional sombrero: vaguely hat-like in shape, it once also reared out of the sea like the crown and brim of a sombrero, until the crown was diminished by quarrying from the 1850s onwards. The reduction can already be seen in this contemporary print from the heyday of the Sombrero trade in 1865, depicting ships crowding round this little island of only 92 acres. It also shows the source of the island’s natural resources, the seabirds wheeling in the air whose accumulated guano provided rich phosphate fertiliser for farming.

As so often with wrecks of ships involved in a particular trade, our wrecks date from the zenith of Britain’s guano interests in Sombrero, very nearly contemporary with the print. Two barques illustrate what must have been a typical route, lost in the Bristol Channel, bound for Gloucester: the Caravan in Walton Bay in 1869, and the Cornwall, sunk following collision off Lundy in 1871. By 1890 the island was effectively ‘quarried out’: centuries of seabird ‘resources’ had been rapidly depleted and dispersed to fuel the needs of American farmers in the 1850s and British farmers thereafter.

We know of 30 wrecks laden with guano, which was normally sourced from bird cliffs and bat caves. I cannot resist telling you, however, that a couple of other wrecks lost in English waters homeward-bound from Islas Lobos de Afuera or Islas Lobos de Tierra off Peru would appear more likely to contain guano from a less common source: from seals.