Green’s Dictionary of Slang

paste-horn n.

[SE pastehorn, a cow’s horn used to hold paste]

the nose.

[UK]H. Mayhew Great World of London I 6: The mouth has come to be styled the ‘tater-trap;’ the teeth, ‘dominoes;’ the nose, the ‘paste-horn’.
[UK]Mayhew & Binny Criminal Prisons of London 6: [as cit. 1856].
[Scot]Stirling Obs. 7 Feb. 8/3: Everything that’s unsichtly the wretches compare / T’ auld Sally M’Whapie’s paste horn.
[UK]Sl. Dict.