Sentence:  It has been stated by trustworthy authorities that certain waters in the lias-formation possess <WSD>scouring</WSD> properties. ... Mr. Clarke likewise mentions two cases. "In one instance," he says, "a large piece of pasture-land was found to <WSD>scour</WSD> the cows kept upon it, to the great loss of the occupier, until he hit upon the expedient of cutting off the supply of spring-water from a neighbouring brook, and confining the supply to the rain-water held in the ditches,—the result of which has been that very little of the disorder has since appeared upon the land referred to.nb..." 
Meaning of the word marked with <WSD> tags:  To (cause livestock to) suffer from diarrhoea or dysentery.