Glaciology

A glacier is a budget kept in ice: what falls at the top against what melts at the bottom, with everything in between decided by that difference. Halfway down is la boca del glaciar, the opening where the meltwater stream comes out, and la boca is a word Spanish sends a long way from any face. It is the mouth of a person or an animal. It is the mouth of a river, la boca del Ebro, and the opening of a cave, a tunnel or a glacier. In a city it is la boca de metro, the staircase down into the underground, and la boca de incendios, the hydrant on the pavement. And it is the opening of a jar or a bottle. English uses « mouth » for the first two, then changes to « entrance », « hydrant » and « neck ». Spanish asks only whether something goes in or comes out.