Half the glazing putty has dried hard and crumbled until the cold wind whistles inside.

Rub talcum powder on your hands (to prevent sticking), then work the mixture by hand until it has the consistency of glazing putty.

Glazing putty is traditionally made by mixing a base of whiting (finely ground chalk) with linseed oil in various proportions.

Glazing putty, consisting of a paste of chalk powder and linseed oil, is a sealant for glass windows that hardens within a few weeks of application and can then be painted over.