The Compleat Fortune-Teller was an old thick volume, which lay on a table at her elbow, so worn by pocketing that the margins had reached the edge of the type. Tess took it up, and her mother started.
Tess's mother demonstrates her belief in the Compleat Fortune-Teller, firstly, by insisting that it be lodged outside the house because of its formidable power. This is the reason she tells to take the book "to the outhouse" where Tess stuffs it back in its place in the thatch of the roof. Secondly, shes shows faith in it by consulting it to make her decisions regarding Tess's activities.