The word exposure expresses the purpose of unmasking an imposture. In a masonic context, it is applied to printed matters (newspapers' articles, books or pamphlets) issued in order to make money, to attain celebrity or to hurt Freemasonry by publicizing information, especially of a ritualistic nature, that was either obtained by illicit means or divulged by a renegade who was once a freemason. These can be termed 'genuine' exposures. But some pamphlets issued in England as well as in France during the 18th century are little else than the product of the imagination of their authors. These are 'fancy' exposures, not necessarily printed with a blamable intention but as a practical joke played on credulous readers or to put them off the scent, in which case the authors may well have been freemasons. A masonic student can quickly recognize whether a contemporary exposure is genuine or not. It is often difficult even for an expert to appreciate the genuineness of an exposure of the 18th century. Both kinds of masonic exposures may include either catechisms (that is, a masonic catechetical dialogue) or narratives, or both.

The first series of English masonic exposures comes to an end with the publication of Samuel Prichard's Masonry Dissected in October 1730. The second series starts with the publication of Three Distinct Knocks (April 1760) and of Jachin and Boaz (March 1762)[iv]. '[They] show a certain development having taken place' wrote John Hamill with a remarkable talent for understatement (The Craft, 1986, p. 65). This thirty-year gap is an interesting and hitherto unexplained fact. Early English exposures belonging to the first series together with transcripts of early manuscript catechisms have been published in Early Masonic Catechisms, as mentioned above. Some exposures of the second series have been reproduced in facsimile or transcribed in books or pamphlets.