See A Treatise on White Magic, published in 1934, beginning on page 333, where the following statements appear:
It might be noted here that three great discoveries are imminent and during the next two generations will revolutionise modern thought and life.
One is already sensed and is the subject of experiment and investigation, the releasing of the energy of the atom. This will completely change the economic and political situation in the world, for the latter is largely dependent upon the former. Our mechanical civilisation will be simplified, and an era ushered in which will be free from the incubus of money (its possession and its non-possession), and the human family will recognise universally its status as a bridging kingdom between the three lower kingdoms of nature and the fifth or spiritual kingdom. There will be time and freedom for a soul culture which will supersede our modern methods of education, and the significance of soul powers and the development of the superhuman consciousness will engross the attention of educators and students everywhere.
A second discovery will grow out of the present investigations as to light and colour.
The third development, which will be the last probably to take place, will be more strictly in the realm of what the occultists call magic. It will grow out of the study of sound and the effect of sound, and will put into man's hands a tremendous instrument in the world of creation.