The Physical Phenomena Popularly Classed Under The Head Of Spiritualism investigates the purported physical manifestations associated with spiritualism, examining claims of ectoplasm, spirit photography, and other phenomena attributed to the supernatural. The book seeks to provide a rational or scientific explanation for these occurrences, scrutinizing the evidence and methods employed by spiritualists. It aims to differentiate between genuine physical events and potential fraud or misinterpretation within the context of late 19th and early 20th-century spiritualist movements.

This work is regarded as a critical examination of spiritualist claims from a scientific and rationalist perspective. It is likely to appeal to readers interested in the history of pseudoscience, the psychology of belief, and the debunking of paranormal phenomena. The book's approach is analytical, focusing on empirical evidence and logical reasoning to dissect the claims made by spiritualists. It contributes to the historical discourse on the intersection of science, belief, and the unexplained.