This volume is the most recent in the "Treasures from the Past" series published by Silkworm Books Co., a series that deserves credit for bringing to life many episodes of Southeast Asian history -- especially 17th-century Siam (now known as Thailand). Michael Smithies has done an important service for the English-speaking readership -- translating the original texts (generally in French), which themselves are difficult to find.
S.J. Marcel Le Blanc's testimony is particularly interesting and valuable, as he happened to be an eyewitness to the cataclysmic events of the 1688 Revolution in Siam and its aftermath. As a Jesuit invited by King Narai to promote the study of mathematics and astrology, he, of course, sees through Jesuit lenses, but was not so much directly involved in the unfolding of the drama as some of his colleagues were.
The back cover of this edition questions Le Blanc's impartiality: It objects to his expression of horror at the overthrow of King Narai and finds Le Blanc nurturing some contempt regarding the other group of Catholics in Siam at the time, namely the French missionaries. Nevertheless, at the end, it recognizes that Le Blanc's narrative is an "important historical document."