What is a horse latitude?

A horse latitude is an area of high pressure and low winds that exists at about 30 degrees north latitude and 30 degrees south latitude. Early sailors dreaded these parts of the sea because the winds would become unpredictable, with periods of total calm. Particularly near Bermuda, ships were often stopped in their tracks when the winds gave out. To conserve the crew’s water supply, one survival tactic for a becalmed ship was to abandon any horses on board by letting them die of thirst or tossing them overboard. There were reports that the seas in these areas were “strewn with bodies of horses,” and hence the name “horse latitudes.”