1741

In the book, 1741 serves as a historical precedent in an argument about the tsunami risk posed by a possible collapse of La Palma’s volcanic flank. The year anchors a concrete example of a volcanic event generating destructive waves, while the comparison also underscores the difference between evidence that such disasters can occur and uncertainty about when a future one might happen.

The 1741 precedent

Stanley Frost cites the eruption of Oshima-Oshima in Japan in 1741, saying it triggered waves thirty metres high. The account gives no further detail about the eruption or its effects; its relevance lies in the scale of the waves and their connection to a volcanic event.

Comparison with other disasters

Frost places 1741 alongside the 1888 collapse of Ritter Island in New Guinea. He contrasts both historical examples with the potential La Palma landslide, arguing that Ritter Island involved barely one per cent of the falling rock that could descend from La Palma’s flank. In this sequence, 1741 is one point in a comparison intended to make the danger of a much larger collapse legible.

What the date establishes

The historical example supports the possibility that volcanic activity or collapse can generate exceptionally high waves; it does not establish when a similar disaster might occur at La Palma. The surrounding discussion distinguishes the perceived seriousness of the hazard from the uncertain timing of any future collapse, which could lie decades or centuries away.