This publication explores the rationale behind artist Harriet Bart's use of the recurring image of the plumb bob in conceptually-based installations such as Pendulum (2003) and Requiem (2003-11). The book contains a mixture of quotations and original prose by the artist reflecting on the plumb bob’s history, use, and metaphorical meanings. Several illustrations of plumb bobs accompany the text. Also included is a facsimile letter on the history of the plumb bob. The text was set in Koch Antiqua and FF Meta and printed letterpress with the illustrations on 200gsm Fabriano Artistico. The binding features brass covers with steel hinges at the edges, and the front cover is engraved with the chemical symbol for lead [Pb]. The book is housed in a hinged case of beech wood with covers of aluminum and brass hardware cloth. A metal clasp closure secures the book in the case.