world, and finally make such wasteful wars
impossible. A mere catalogue of Christopher Wren's conjectures,
experiments, and inventions, made while he was an Oxford student, would
more than fill the space I have at command.

At the age of twenty-four he was offered a professorship of astronomy at
Oxford, which he modestly declined as being above his age, but
afterwards accepted. His own astronomy was sadly deficient, for he
supposed the circumference of our earth to be 216,000 miles. This,
however, was before Sir Isaac Newton had published the true astronomy,
or had himself learned it.

After a most honorable career as teacher of science at Oxford, he
received from the restored king, Charles II., the appointment of
assistant to the Surveyor General of Works, an office which placed him
in charge of public buildings in course of construction. It made him, in
due time, the architect-general of England, and it was in that capacity
that he designed and superintended very many of the long series of Works
mentioned above. There never was a more economical appointment. The
salary which he drew from the king appears to have been two hundred
pounds a year, a sum equal perhaps to four thousand of our present
dollars. Such was the modest compensation of the great architect who
rebuilt London after the great fire.

That catastrophe occurred a few years after his appointment. The fire
continued to rage for nearly four days, during which it destroyed
eighty-nine churches including St. Paul's, thirteen thousand two hundred
houses, and laid waste four hundred streets.

Christopher Wren was then thirty-five years of age. He promptly
exhibited to the king a plan for rebuilding the city, which proposed the
widening and straightening of the old streets, suggested a broad highway
along the bank of the river, an ample space about St. Paul's, and many
other improvements which would have saved posterity a world of trouble
and expense. The government of the dissolute Charles was neither wise
enough nor strong enough to carry out the scheme, and Sir Christopher
was obliged to content himself with a sorry compromise.

The rest of his life was spent in rebuilding the public edifices, his
chief work being the great cathedral. Upon that vast edifice he labored
for thirty-five years. When the first stone of it was laid, his son
Christopher was a year old. It was that son, a man of thirty-six, who
placed the last stone of the lantern above the dome