It's most likely the powder magazine, merchant vessels run heavily armed.

很可能是火药库，商船一般都有很好的武装。

" He's in a hurry. We'd — " then I saw another man, an oldish man running heavily, clutching a stick, and a boy naked from the waist up, clutching his pants as he ran.

“他很着急。我们会——” 然后我看到另一个男人， 一个老男人， 他手里拿着一根棍子， 沉重地跑着， 还有一个男孩子上半身一丝不挂， 边跑边抓着裤子。