An extensive and scholarly study of the Galilean controversy as it ran its course through the first decades of the 17th century concentrates on its clerical and legalistic aspects and provides some clarifying historical perspectives. De Santillana takes up his story in 1610 when Galileo was already a well known scientist and mathematician and convinced of the validity of Copernicus' theories. At that point Galileo employed the telescope to further his own proof of a sun centered world. But an unaccepting clergy, aptly called the first bewildered victims of the scientific age, came in the discovery's wake to swamp it temporarily by charging Galileo with heresy. The course of Galileo's trial is familiar, but it is amplified here to give a rather complete view of the prevailing personal and social conditions that had their bearing on it and which made it more than purely theological. Competent examinations of contemporary legal and theological codes raise the questions of the validity of the injunction against Galileo and of whether or not Galileo could have managed the priests so that he could have been left free to work unhampered. There are also his feelings as an ""anticlerical Catholic"" which were not unique at the time and that may have led him to the submissive course he chose to take. An interesting character study in terms of social milieu. Of definite reference value.