Casting method and pack

A method of making casts of footprints, tyre marks or other impressions or marks which comprises: providing a watertight pack made of a flexible and substantially water-impermeable material and having two compartments enclosed therein separated by means which may be removed to allow the contents of the compartments to be mixed; one of said compartments containing Plaster of Paris or similar water-settable inorganic moulding material and the other containing water for setting the moulding material, or one of said compartments containing a room temperature - curable fluid silicone and the other containing a curing agent or accelerator for the silicone; removing the separating means and mixing the contents of the two compartments within the pack; dispensing the mixture from the pack into or onto the impression or mark and allowing the mixture to set to form a cast.