E. Cobham Brewer 1810–1897. Dictionary of Phrase and Fable. 1898.
Blush.
At the first blush. At the first glance; speaking off-hand without having given the subject mature deliberation. The allusion is to blushing at some sudden or unexpected allusion; the first time the thought has flashed into your mind.
1
To put to the blush. To make one blush with shame, annoyance, or confusion.
2
“England might blush in 1620, when Englishment trembled at a fool’s frown [i.e. James I.], but not in 1619, when an enraged people cut off his son’s [Charles I.] head.”—Wendell Phillips: Orations, p. 419.
