On the Navy-Boards
Demosthenes
Demosthenes. Vol. I. Olynthiacs, Philippics, Minor Public Speeches, Speech Against Leptines, I-XVII, XX. Vince, J. H., translator. Cambridge, MA: Harvard University Press, 1930 (printing).
Thus, if you want a hundred war-galleys the cost of each will be covered by the sixty talents and there will be twelve trierarchs for each; if you want two hundred, there will be thirty talents to cover the cost and six persons to serve as trierarchs; if you want three hundred, there will be twenty talents for the cost and four persons to serve.