1889        J., F.H. "Negro Music of the United States." In _A Dictionary of Music and Musicians_, ed. by Sir George Grove. Vol. 4. London: Macmillan. 728-730.

Early edition of Grove's Dictionary of Music and Musicians. Reflects the "common knowledge" about African-American musical style that probably would have informed C. Sharp and Arnold (w/ Bullen) in their comments from their collections.

Just one excerpt here on work-singing, by stevedores and firemen:

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They [African-Americans] have songs for all occasions where they move in concert, such as loading or unloading ships, or working at the pumps of a fire engine. Their rhythmic sympathies are most strongly active on these occasions. Often one of a gang acts as a precentor, giving a line or two by himself, and the chorus coming in with the refrain. This leader, when his supply of lines gives out or his memory fails, resorts to improvisation.
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No mention of any sailors' songs in this volume.