Definition of "appositeness"

There is a want of appositeness and accuracy in the first sentence of this extract, which renders it somewhat difficult to determine whether the author designed it as a single proposition, or as a series of independent propositions.

1840, Abel Upshur, A Brief Enquiry into the Nature and Character of our Federal Government, Campbell, page 62

For two years more he lingered, sinking slowly into unconsciousness and imbecility. Sometimes, propped up in his chair, he would be heard to murmur, with unexpected appositeness, the words of Samson [...]

1921, Lytton Strachey, Queen Victoria