As`cer*tain" (&?;), v. t. [imp. & p. p. Ascertained (&?;); p. pr. & vb. n. Ascertaining.] [OF. acertener; a (L. ad) + certain. See Certain.] 1. To render (a person) certain; to cause to feel certain; to make confident; to assure; to apprise. [Obs.]

When the blessed Virgin was so ascertained.
Jer. Taylor.

Muncer assured them that the design was approved of by Heaven, and that the Almighty had in a dream ascertained him of its effects.
Robertson.

2. To make (a thing) certain to the mind; to free from obscurity, doubt, or change; to make sure of; to fix; to determine. [Archaic]

The divine law . . . ascertaineth the truth.
Hooker.

The very deferring [of his execution] shall increase and ascertain the condemnation.
Jer. Taylor.

The ministry, in order to ascertain a majority . . . persuaded the queen to create twelve new peers.
Smollett.

The mildness and precision of their laws ascertained the rule and measure of taxation.
Gibbon.

3. To find out or learn for a certainty, by trial, examination, or experiment; to get to know; as, to ascertain the weight of a commodity, or the purity of a metal.

He was there only for the purpose of ascertaining whether a descent on England was practicable.
Macaulay.

• To find out; to discover, learn, or establish.
       As soon as we ascertain what the situation is, we can plan how to proceed.