These letters relate to Elements of Internal Combustion Turbine Theory by Adams, H.T. They comprise 1 typed letter signed from [? Wein, R.A.] to Adams, H.T, 1 typed letter signed from Welch, H.G.G. to Adams, H.T., 1 typed letter signed from Rhoden, H.G. to Kendon, F.H., 1 carbon typed letter to Rhoden, H.G. and 1 autograph letter signed from Rhoden, H.G. Includes reports by H.G. Rhoden.