Generally the parts taken up by the congregation are sung in a three-part harmony, the women singing the soprano and a transposed tenor, the men with high voices singing the melody, and those with low voices a thundering bass. In a few of these songs, however, the leading part is sung in unison by the whole congregation, down to the last line, which is harmonized. The effect of this is intensely thrilling. Such a hymn is "Go down, Moses." It stirs the heart like a trumpet call. "Singing Johnson" was an ideal leader, and his services were in great demand. He spent his time going about the country from one church to another. He received his support in much the same way as the preachers--part of a collection, food and lodging. All of his leisure time he devoted to originating new words and melodies and new lines for old songs. He always sang with his eyes--or, to be more exact, his eye--closed, indicating the _tempo_ by swinging his head to and fro. He was a great judge of the proper hymn to sing at a particular moment; and I noticed several times, when the preacher reached a certain climax, or expressed a certain sentiment, that Johnson broke in with a line or two of some appropriate hymn. The speaker understood and would pause until the singing ceased. As I listened to the singing of these songs, the wonder of their production grew upon me more and more. How did the men who originated them manage to do it? The sentiments are easily accounted for; they are mostly taken from the Bible; but the melodies, where did they come from? Some of them so weirdly sweet, and others so wonderfully strong. Take, for instance, "Go down, Moses." I doubt that there is a stronger theme in the whole musical literature of the world. And so many of these songs contain more than mere melody; there is sounded in them that elusive undertone, the note in music which is not heard with the ears. I sat often with the tears rolling down my cheeks and my heart melted within me. Any musical person who has never heard a Negro congregation under the spell of religious fervor sing these old songs has missed one of the most thrilling emotions which the human heart may experience. Anyone who without shedding tears can listen to Negroes sing "Nobody knows de trouble I see, Nobody knows but Jesus" must indeed have a heart of stone. As yet, the Negroes themselves do not fully appreciate these old slave songs. The educated classes are rather ashamed of them and prefer to sing hymns from books. This feeling is natural; they are still too close to the conditions under which the songs were produced; but the day will come when this slave music will be the most treasured heritage of the American Negro.