The book "A Practical Outline of Some Principles of Hymn Singing" by Robert Bridges is a detailed study of important aspects of hymn singing in religious church services. The author analyzed and explained the basic principles and techniques of singing hymns from the point of view of musical theory and practice. The book contains practical advice that will help the reader better understand and perform hymns with spiritual expressiveness and faithfulness to the musical style. "A Practical Sketch of Some Principles of Hymn Singing" is a must-have resource for anyone interested in music and religion.