Copy letter from James Hopwood Jeans, Secretary of the Royal Society; to P. A. Mainstone Esq.; Old Buildings, University College of North Wales, Bangor Discusses P. A. Mainstone's application for a grant for a transformer, and advises him that it would be better to write to the Royal Institution, and if they deem a transformer necessary to his work, to forward their letter back to the Royal Society to better support a grant application. 9 October 1925