About, and the participial prepositions concerning, respecting, regarding, mean with reference to.
Phrase prepositions.
317. Many phrases are used as single prepositions: by means of, by virtue of, by help of, by dint of, by force of; out of, on account of, by way of, for the sake of; in consideration of, in spite of, in defiance of, instead of, in view of, in place of; with respect to, with regard to, according to, agreeably to; and some others.
318. Besides all these, there are some prepositions that have so many meanings that they require separate and careful treatment: on (upon), at, by, for, from, of, to, with.
No attempt will be made to give all the meanings that each one in this list has: the purpose is to stimulate observation, and to show how useful prepositions really are.
At.
319. The general meaning of at is near, close to, after a verb or expression implying position; and towards after a verb or expression indicating motion. It defines position approximately, while in is exact, meaning within.
Its principal uses are as follows:—
(1) Place where.
They who heard it listened with a curling horror at the heart.—J. F. Cooper.