that the sole regenerating power of the universe is
heat; yonder furnace shall supply it, and then Hubert de Dreux is his
master's equal!"

* * * * *

The short November day was drawing to a close, when, after carefully
tending the wounded sheriff, and leaving such instructions with the
Abingdon leech as he judged sufficient for his patient's well-doing,
Roger Bacon again mounted his palfrey, and turned its head in the
direction of Oxford. He was unwilling to be a loiterer after dark, and
his beast was equally desirous to be once more comfortably housed, so
that his homeward journey was accomplished even more rapidly than his
morning excursion; and barely an hour had elapsed when the Friar drew
the rein at the foot of the last gentle eminence, close to which lay the
walls of the cloistered city. To give the animal breathing-space, he
rode quietly up the ascent, and then paused for a few moments before he
proceeded, his mind intent on subjects foreign to the speculations of
all his daily associations.

Suddenly, as he mused on his latest discovery and calculated to what
principal object it might be devoted, a stream of fiery light shot
rapidly athwart the dark, drear sky, and before he had space to think
what the meteor might portend, a roar as of thunder shook the air, and
simultaneous with it, a shrill, piercing scream, mingled with the
fearful sound; then burst forth a volume of flame, and on the wind came
floating a sulphurous vapor which, to him alone, revealed the nature of
the explosion he had just witnessed.

"Gracious God!" he exclaimed, while the cold sweat poured like
rain-drops down his forehead, "the fire has caught the fulminating
powder! But what meant that dreadful cry? Surely nothing of human life
has suffered! The boy Hubert--but, no--he was at work at the further
extremity of the building. But this is no time for vain, conjecture--let
me learn the worst at once!"

And with these words he urged his affrighted steed to its best pace, and
rode rapidly into the city.

All was consternation there: the tremendous noise had roused every
inhabitant, and people were hurrying to and fro, some hastening toward
the place from whence the sound had proceeded, others rushing wildly
from it. It was but too evident that a dreadful catastrophe, worse even
than Bacon dreaded, had happened. It was with difficulty he made his way
through the crowd, and came upon the ruin which still b