I was cogitating what the mystery might be, and determined Catherine should never suffer to benefit him or any one else, by my good will; when, hearing a rustle among the ling, I looked up and saw Mr. Heathcliff almost close upon us, descending the Heights.
There are no more uses of "cogitate" in the book.
Show samples from other sources
But, exhausted by his cogitation, he’d have energy left for only one word, the name of the flower.
Gail Carson Levine -- Ella Enchanted
The average squirrel cogitation goes something like this: I wonder what there is to eat.