Green’s Dictionary of Slang

a general excl. expressing incredulity or derision, i.e. don’t exaggerate!

1841		Punch I 60/2: Draw it mild! as the boy with the decayed tooth said to the dentist.
1842		Boston Satirist (MA) 21 Oct. n.p.: Draw it mild and mind your eyes!
1843		Satirist & Sporting Chron. (Sydney) 18 Feb. 3/3: Oh! Betty Martin [...] your son will be the death of us — what a boy he is! — James, James, draw it mild.
1850		F.E. Smedley Frank Fairlegh (1878) 18: Draw it mild, old fellow!
1854		Anti-Slavery Bugle (New Lisbon, OH) 8 Apr. 4/4: Draw it mild, Charley [...] Don’t pile up all the agony today.
1860		Melbourne Punch 9 Aug. 7/1: ‘Slangiana’ [...] ‘Yes, draw it mild,’ he coaxing said.
1865		Trollope Can You Forgive Her? 36: ‘Come, Bott, draw it mild,’ said Calder Jones, whose loyalty was shocked by the utter Manchesterialism of his political friend. [Ibid.] 192: ‘Come, Athenian, draw it mild,’ said Maxwell.
1877		J. Greenwood Dick Temple I 255: ‘Draw it mild, Eggy, old boy,’ in murmured remonstrance from Mr. Muggeridge.
1883		Little Falls Transcript (MN) 28 Sept. 7/3: ‘Draw it mild, old lady,’ he said.
1893		Witchita Daily Eagle (KS) 9 July 11/3: ‘Draw it mild, Dick,’ I suggested .
1898		H. Lawson ‘“Dust Thou Art”’ in Roderick (1972) 316: Oh, Lord! Draw it mild, Jack.
1902		Bulletin (Sydney) 18 Oct. 15/2: Mills smiled derisively – ‘Oh! draw it mild.’ / Randall jumped up. ‘I’ll bet you five pound it’s true.’.
1907		D. Stewart Shadows of the Night in Illus. Police News 3 Aug. 12/3: ‘I say, gal, draw it mild — this ere’s comin’ it a bit too thick’.
1910		Magnet 10 Sept. 13: Here, draw it mild!
1918		K.F. Purdon Dinny on the Doorstep 239: Oh come, draw it mild, you know!
1928		(con. 1918) L. Nason Top Kick 29: Draw it mild, draw it mild!
1942		(con. 1890s) S. O’Casey Pictures in the Hallway 286: Eh, you, he said to the lissome lassie, draw it mild an’ let the woman have her say.
1961		‘Frank Richards’ Billy Bunter at Butlins 119: ‘Oh, draw it mild,’ snapped Bunter.