"sowies," and "portculize," and springwalls, or springald's, or
springalls, mediaeval balistas for throwing heavy stones and darts.
But Hogg did not know or guess what a springwall was. In his stanza
xiii. (in the MS. given to Laidlaw), Hogg wrote -


With springs; wall stanes, and good o'ern
Among them fast he threw.


Scott saw the real meaning of this nonsense, and read -


With springalds, stones, and gads o' airn.


In his preface he says that many words in the ballad, "which the
reciters have retained without understanding them, still preserve
traces of their antiquity." For instance, springalls, corruptedly
pronounced springwalls. Hogg, hearing the pronunciation, and not
understanding, wrote, "with springs: wall stanes." A leader would not
throw "wall stanes" till he had exhausted his ammunition. Hogg heard
"with springwalls stones, he threw," and wrote it, "with springs: wall
stones he threw."

Hogg could not know of Auld Maitland "and his three noble sons" except
through an informant familiar with the Maitland MSS. in Edinburgh
University Library. On the theory of a conspiracy to forge, Scott
taught him, but that theory is crushed.