_Burnet._ [The Countess of Dysert] was a woman of great beauty, but of far greater parts.

...

She had studied not only divinity and history, but mathematics and philosophy.

She was violent in everything she set about, a violent friend, but a much more violent enemy.

...
[When Lauderdale] was prisoner after Worcester fight, she made him believe he was in great danger of his life, and that she saved it by her intrigues with Cromwell .-- _Swift._ Cromwell had gallantries with her.
P.248.