Because you're a coward, sir.

There!" "Ah-h-ah!" growled the other men in chorus, as they glared at the lad.
"Then take a coward's blow," cried Ralph; and he struck the man with all his might across the face, using the back of his hand.
There was another growl from the men, but no one spoke, and Mark Eden turned again, and strode down the hill, while the men untied and coiled up the ropes, and slowly followed their young master down the slope, and then up once more toward the Castle, Nick Garth shaking his head a good deal, and looking puzzled, and a great deal interested in the blood which he kept smudging off, first with one hand, and then with the other, from his face.
"Here," he cried at last, as Ralph disappeared through the gateway, "what's best to stop this here?
I can't go with it all tied up." "Bucket o' water from the well," said Ram Jennings, grinning.

"Say, Nick, he aren't such a coward, arter all." "No," growled Nick, after a double wipe; "and, for such a little 'un, he can hit hard.".