This section is from the book "Ancient Legends, Mystic Charms, And Superstitions Of Ireland", by Jane Francesca Wilde. Also available from Amazon: Ancient Legends, Mystic Charms, And Superstitions Of Ireland.
" Who will heal me from the red, thirsty, shivering, cold disease that came from the foreigner, and kills people with its poisonous pain ?" " The prayer of Mary to her Son, the prayer of Columbkill to God; these will heal thee. Amen."
Say this oration three times over the patient, making the sign of the cross each time-
Then take butter, breathe on it quite close, and give it to the person to chafe himself therewith.
To ascertain if he will recover, put a handful of yarrow in his hand while he is sleeping ; if it is withered in the morning, he will die ; but if it remains fresh, the disease will leave him.