The reference is to the process of "horning" described on p. 16.
Recovery takes place after a few weeks by the tissues "horning over," as in injuries attended by the same process.
Horning; a legal demand for payment of a debt under threat of imprisonment and being proclaimed rebels.
God shall send unto you messengers who will not be afraid of horning, nor yet of banishment.
Horning Ferry, a well-known waterside resting-place, may be taken as a typical feature of village life in these parts.
Then the river turns still more sharply to the left, and we sailed due south, after having come due north by Horning.
At Horning village, the “New” Inn deserves mention, and boats can be procured there.
So by wood and mere and sighing reed we pass with many a twist and turn until we reach the hostelry of Horning Ferry.
Darnley also told the story of horning Moray to a servant of his, which Moray is privy unto.
Pascoe and Horning then carry the inanimate form of Shawn into the room behind, while Carve hovers about uselessly.