Sentence:  The boils called <WSD>"sand boils</WSD>", which form on the front of the knee, are generally produced by small particles of sand being rubbed beneath the skin when the men are kneeling to holystone the decks. Very troublesome sores are thus produced. Great care should, therefore, be taken never to kneel with the bare knees upon a sanded deck. In treating a <WSD>sand boil</WSD>, all particles of sand must be removed, wet compresses applied for a day or two, the leg kept at rest, dry lint and adhesive plaster being afterwards used. 
Meaning of the word marked with <WSD> tags:  A boil which forms when sand particles enter and irritate the skin.