Various, Chambers's Journal of Popular Literature…
“ Take a filled ale-jug, or the well-known 'pewter' of a tavern or public-house, and pour out gently into a glass: scarcely any froth is produced. Pour out the self-same liquor from the self-same vessel in a stream several inches high, and you produce a foaming 'head,' which to the eye seems to be a substance quite different from ale or beer. Open a bottle of lemonade or ginger-beer, of soda-water{448} or seltzer-water, and pour out the contents into a glass; the formation of froth is so rapid and abundant that the glass appears full when it really contains but a small quantity of liquid. ”
