d to glory;
and moreover the time, which Cornelius had spent in literature, would
not be absolutely lost for war. He added, that the Duke of Weymar being
the greatest and most experienced general of his age, he was very
desirous that his son should serve under such an able master; and that
he would send him with a reinforcement that was marching to that
Prince, who, he hoped, would assist him with his advice. Cornelius was
very well received by the Duke[742]; and for some time kept up an exact
correspondence with his father by letters, who complimented him on his
diligence in writing. The Duke of Weymar promised to advance him, if he
paid a proper regard to his father's counsels. Cornelius was by nature
so inconstant, that he soon took a dislike to the army: he had even
thoughts of returning to his father, who diverted him from it as a step
which would dishonour him.

On the Duke of Weymar's death, Reigersberg advised Cornelius to write
that Prince's history. Young Grotius mentioning this project to his
father, he pressed him to execute it, because it would give him an
opportunity of expressing his gratitude to a Prince who had laid him
under great obligations, and done such important services to Sweden.
Besides, this work would be of use to the author, by obliging him to
study the Art of War, in order to speak of it properly. Cornelius
contented himself with projecting this design[743]: he changed his
service, and entered into the Marshal de Chatillon's army, in which he
continued not long: he made the campaign of 1640, in quality of Cornet
in the Colonel's company of a German regiment of horse in the French
service. Soon after he got a company: however he wanted to serve in the
Valtoline[744]. He had not been long there before he took a fancy to
enter into the Venetians service; and, without consulting his father,
went to Venice to make his contract with them: but it is probable they
could not agree; for Grotius writes[745], July 16, 1644, "Cornelius will
return from the Antenorides without doing any thing." This fickleness of
temper much displeased Grotius[746], who in the latter part of his life
spoke of his son with great indifference.

In the sequel, when the States of Holland wanted to indemnify such as
were unjustly persecuted during the overgrown power of the
Stadtholders[747], they gave Cornelius Grotius a company in the guards;
to Peter, a troop of horse; and to Mombas, their brother-in-law, a
regiment; wit