For cleaning glazed terracotta floor tiles, a rub with a dry or slightly damped flannel is all that is necessary. Unglazed floor tiles occasionally present a white scum on the surface, caused by the evaporation of the lime ami cement used in the foundations. In caseswhere the tiles have been laid on new foundations, this scum may continue appearing for some months. The floor is not injured by this, and the scum may easily removed. Floor tiling should be cleaned two or three times a week with soft soap dissolved in tepid water and applied with a hand scrubbing-brush. Paint spots or similar stains, and also cement murks, may be removed by pouring on them a small quantity of sulphuric acid diluted with an equal quantity of water and allowing it to remain for a few hours. It should then be washed off and, if necessary, again applied till the stain lias disappeared. For removing ink stains, use nitrous acid in place of sulphuric acid. Particular care should be taken when using these acids, as they will burn both hands and clothes.

A piece of old flannel may be used for washing the acid from the tiling.