To Keep Flies Out of a Room
April 12th, 2018
Put a few drops of oil of lavender on a sponge placed in a saucer of hot water. This will give out a scent which flies dislike. If you do not wish to try it in the house, put the sponge on a table on the porch if the flies are troublesome there.
Source: 1001 Household Hints, Ottilie V. Ames