Banjo History | 1750-1850 "Transmission Period"

In banjo researcher George R. Gibson's 2002 article 'Gourd Banjos: from Africa to the Appalachians' note the following citation:

'Banjo playing in Tidewater Virginia is described in the Journal and Letters of Philip Vickers Fithian. Fithian was a tutor at Nomini Hall, owned by Robert Carter. The Carter family was one of the most prominent in Virginia. Carter employed, in addition to Fithian, both a dancing master and a music tutor. Fithian's diary entry for February 4, 1774, included the following about two of his pupils:'

"This evening, in the School-Room, which is below my Chamber, several Negroes & Ben, & Harry are playing on a banjo and dancing!"

http://www.banjohistory.com/article/detail/1_gourd_banjos_from_africa_to_the_appalachians

This account, when considered along with the late 18th-century description of a Mr. Rector near Maysville, Kentucky (presumably a white person) who made deer gut banjo strings, convinces me that the banjo had been largely transmitted into "white" rural society by 1800. Numerous other accounts (too numerous to list in detail) written by whites during the period before 1800 all mention the banjo but briefly--and casually--as if describing it to the common reader would be tedious and redundant. Therefore, it is only logical to assume that by 1750 the instrument was already widely known in every colony--especially around the Chesapeake Bay, the low country of the Carolinas and the expanding western frontiers.

In spite of it's widespread popularity among rural Americans, the banjo remained for generations an obscure folk instrument almost exclusively made at home using scrap wood and a hard shell gourd grown in the garden. It wasn't until the 1850s that the more durable "tack-head banjo" (or what is anachronistically referred to as the "minstrel banjo") took over as the popular form. Thus we must also assume that the two earliest undisputed white banjo players, Ferguson and Sweeney, also played on gourd instruments. 

The question of when the transition was made from the banjo as an exclusively African-American instrument to one played by blacks and white alike, to me, has been satisfied by the 18th-century quotations provided in George Gibson's 2000 and 2002 articles cited above: We now know that this occurred, most likely, by 1800.

The question of when and where the transition from a chiefly home-made gourd instrument to the sturdier bentwood hoop designs has, on the other hand, not been clearly answered. Nor has the question of when and where the thickened bass (or 4th) string entered widespread use--I have found no reference to a five string banjo prior to it's sudden emergence in literature and imagery from about the 1830s onward. 

http://banjohistory.com/article/detail/1_gourd_banjos_from_africa_to_the_appalachians