By killing off the watchers over Black Riot one by one they knew that there would come a time when, being able to get no one else to take the risk of guarding the horse and sleeping on that bed before the steel-room door, you would do it yourself; and when that time came they would have had you." "But how?
By what means ?" "By one of the most diabolical imaginable.

Among the reptiles of Patagonia, Sir Henry, there is one--a species of black adder, known in the country as the Mynga Worm--whose bite is more deadly than that of the rattler or the copperhead, and as rapid in its action as prussic acid itself.

It has, too, a great velocity of movement and a peculiar power of springing and hurling itself upon its prey.

The Patagonians are a barbarous people in the main and, like all barbarous people, are vengeful, cunning, and subtle.

A favourite revenge of theirs upon unsuspecting enemies is to get within touch of them and secretly to smear a mixture of coriander and oil of sassafras upon some part of their bodies, and then either to lure or drive them into the forest; for by a peculiar arrangement of Mother Nature this mixture has a fascination, a maddening effect upon the Mynga Worm--just as a red rag has on a bull--and, enraged by the scent, it finds the spot smeared with it and delivers its deadly bite." "Good heaven! How horrible! And you mean to tell me--" "That they employed one of these deadly reptiles in this case?
Yes, Sir Henry.