A dictionary of Proverbs (Oxford Paperback Reference)

A BIRD never flew on one wing
Mainly Scottish and Irish. Now frequently used to justify a further gift, esp. another drink.

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  1721 J. KELLY Scottish Proverbs 308 The Bird must flighter [flutter] that flies with one Wing. Spoken by them who have Interest only in one side of the House. 1824 S. FERRIER Inheritance III. xxxii. ‘The bird maun flichter that flees wi’ ae wing’—but ye’s haud up your head yet in spite o’ them a’. 1914 K. F. PURDON Folk of Furry Farm ii. He held out a shilling to Hughie. ‘A bird never yet flew upon the one wing, Mr. Heffernan!’ said Hughie, that was looking to get another shilling. 1925 S. O’CASEY Juno & Paycock III. 89 Fourpence, given to make up the price of a pint, on th’ principle that no bird ever flew on wan wing. 1980 J. O’FAOLAIN No Country for Young Men iii. I’ll just have another quick one. A bird never flew on wan wing. "food and drink
  

bird see also as good be an ADDLED egg as an idle bird; you cannot CATCH old birds with chaff; the EARLY bird catches the worm; FINE feathers make fine birds; it’s an ILL bird that fouls its own nest; in vain the NET is spread in the sight of the bird.
There are no BIRDS in last year’s nest
Circumstances have altered.

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  1620 T. SHELTON tr. Cervantes’ Don Quixote II. Ixxiv. I pray you go not on so fast, since that in the nests of the last yeere, there are no birds of this yeere. Whilom [formerly] I was a foole, but now I am wise. 1732 T. FULLER Gnomologia no. 4863 There are no Birds this Year, in last year’s Nest. 1845 LONGFELLOW Poems 62 All things are new..even the nest beneath the eaves;—There are no birds in last year’s nest. 1946 H. MCELROY Unkindly Cup I. ii. 23 ‘I am not as bad, or as unfeeling as I sound. It was my memory that was groaning—not the other part of my anatomy.’ ‘“There are no birds in last year’s nests”,’ Bland quoted sententiously. ■ change; circumstances