Benjamin Robbins Curtis, Turner v. Yates — Opinion of the Court
“ Whether Harry was principal or agent, it was competent and important for the plaintiff to prove that he was dealt with and treated as a principal; and there could be no better evidence of it than the correspondence concerning the transaction. On the trial of a commercial cause such a correspondence is not only generally admissible, but it is often the highest evidence of the nature of the acts of the parties and the capacities in which they acted and the relations they sustained to each other. ”
