 Many mediums had used methods of swallowing and regurgitating cheesecloth, textile products smoothed with potato starch and in other cases the ectoplasm was made from paper, cloth and egg white or butter muslin.The Society for Psychical Research investigations into mediumship exposed many fraudulent mediums which contributed to the decline of interest in physical mediumship.In 1907, Hereward Carrington exposed the tricks of fraudulent mediums such as those used in slate-writing, table-turning, trumpet mediumship, materializations, sealed-letter reading and spirit photography.