Sjoerd Spoelstra • Link
Captain Ferrer or Ferrers started out as Montague's "Cornet", and then as his "master of horse".
A Cornet is a low ranking cavalry officer that carried the troop flag (or cornet).
The family name means "horse-shoer and iron worker".
He seems from the diary to be a very dashing fellow, almost literally in the entry of May 19 1661 where he jumps from a balcony on a bet.
To have a "master of horse" at all seems to be somewhat of a luxury item, together with "a French cook" and "and his lady and child to wear black patches".
So maybe the dashing, the drinking, gambling and womanising were all part of the job profile.