Sentence:  These were the two invalids in the starboard sick-berth, whom Padeen had been sitting with. They had been sparring, in a spirit of fun, with <WSD>loggerheads</WSD>, those massy iron balls with long handles to be carried red-hot from the fire and plunged into buckets of tar or pitch so that the substance might be melted with no risk of flame. 
Meaning of the word marked with <WSD> tags:  A metal tool consisting of a long rod with a bulbous end that is made hot in a fire, then plunged into some material (such as pitch or a liquid) to melt or heat it.