Both Uses of

dispose
in
The Witch of Blackbird Pond

"Humph!" With one syllable Matthew disposed of the sacrifice, only a little less sharp than Grandfather's loss,
p. 37.7 *

disposed = put an end to discussion

In the hallway William did not seem disposed to hurry.
p. 228.5 *

disposed = inclined (having a state of mind that favors doing something)

Definitions:

(1) (dispose as in: dispose of the waste)
to throw away
(2) (dispose as in: dispose of the matter)
to settle something so it no longer requires attention
(3) (dispose as in: dispose of the assets)
sell or transfer to another
(4) (dispose as in: disposed the troops along...)
the arrangement, positioning, or use of things
This sense of dispose can be used in the form disposal to indicate that a person can use something as they wish -- as in:
- I am at your disposal.
- She has many assets at her disposal.
(5) (dispose as in: Is she disposed to help?)
inclined (with a tendency to; or in the mood to)

This is usually seen in the form "disposed to..." or "disposed toward..."
(6) (meaning too rare to warrant focus)
meaning too rare to warrant focus:

Less commonly, disposing of can imply killing someone.