The author, William Horatio Clarke has been called "America's Organ Architect" and the book he wrote aims to provide the reader with a brief rendering of the inner-workings of the pipe organ in America in the mid 19th century.
Clarke was building pipe organs at the time of writing of his book and while some of his simplest and smallest instruments survive to this day (less than 10?) some of his lugubrious designs were disasters--I suspect he gained tremendous confidence in his ability to persuade people to buy organs built to his specification and taste and suffered the misfortune associated with those who misinterpret their success with people and committees to such an extent they believe they can build great pipe organs with comparatively little hands-on, practical, wood chips in your face, experience that all great organbuilders share.
A good read...but not useful for any practical purpose aside from the study of 'things' historic.