Apparatus And Experiments On Sound Intensity (1916) - Livres de poche

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: II. EXPERIMENTS ON THE RELATIVE INTENSITY OF SUCCESSIVE, SIMULTANEOUS, ASCEND- ING AND DESCENDING TONES What has preceded seems to deal with the physical principles of constant rotation and of tone production rather than with the psychological properties of tones. However, in psychology as in the other sciences the time has passed when it is possible to perform fruitful experiments on new problems with apparatus that was designed for other problems and that is now listed in the catalogs of dealers in psychological apparatus. When the apparatus had been developed to the point at which it seemed profitable to begin the psychological experiments for which it had been designed, it was decided to begin with the simplest of tone intensity problems. This seemed to be the influence of the method of presentation upon the intensity relations between tones. At the close of the experiment the "simplicity" was decidedly less simple than it appeared to be at the beginning. The reason why it was necessary to restrict the experiment to the relative intensity instead of working with absolute intensities and then from these deriving the relative values, was mainly due to the fact that no absolute standard which could be used was available. The Bureau of Standards at Washington does not furnish a tone of unit intensity which may be used as a standard. Professor A. G. Webster has defined a standard of tone intensity but to calibrate the intensities used in this experiment in terms of this standard would require an interferometer and a degree of technical skill in the manipulation, which would require months to develop. A simpler device is needed. The writer hopes, in the near future, to design an electrically driven fork which may be used as a standard for tone intensities which will be sui...