It is, I suppose, known to most of those present in this lecture hall that the Royal Aeronautical Society was founded in 1866–to be exact the first preliminary meeting was held, under the chairmanship of the Duke of Argyll, on January 12th, though the first meeting of members did not take place until the 27th of June following. It is, therefore, within a few days of 70 years ago that the Society came into being. That is a full and honourable age, and with it goes the distinction–in which we are entitled to take some pride–of being the oldest Aeronautical Society in the world. The anniversary may not arouse the enthusiasm usually associated with the more youthful glamour of a silver or a diamond jubilee. On the other hand it denotes another decade of progress in the growth of aeronautical science, and of even more marked developments in the application of that science, on which grounds alone it deserves passing notice.

The present 2nd Series of the “Rendiconti sperimentali del Laboratorio di Aeronautica del Reale Istituto Superiore di Ingegneria di Torino” follows on the 1st Series published in April, 1934. It includes:—

1. (1) Description of a new six-forces balance.

2. (2) Statement and discussion of the results of the tests on :—

   1. (a) a 600 mm. wind tunnel with open jet and return flow, with the object of deter- mining the influence on the steadiness and distribution of velocity of the stream in a cross-section of the jet of various details of design (dimensions of the cells of the honeycomb, cascades, etc.) and the diffusion of the portion of the airstream undisturbed by the air carried along by the jet owing to the effects of viscosity.

   2. (b) on fifteen models of wings.

   3. (c) on three motor car models.

   4. (d) on an airscrew model mounted at various lateral angles to the relative asymptotic wind (airscrew in a side wind).

   5. (e) on three models of tail plane in the presence of an airscrew.

The last-mentioned tests on tail planes are part of a series of tests still being carried out with the financial assistance of the Directorate of Research and Experiments of the Air Ministry at the suggestion of General Crocco, with the object of determining the influence of the working airscrew on the aerodynamic characteristics of tail surfaces.