Letter from Willem Henri Julius, Utrecht, to Prof J [Joseph] Larmor, Cambridge He refers to the February number of 'The Observatory' in which Larmor was struck by Maunder's paper on connections between terrestrial magnetism and the Sun. He sends his own publication in which number 7 has suggestions on attacking the problem, but this was published before Maunder's results were known. These results agree well with the observation that both solar and terrestrial distrubances are associated with irregularities in the radiation field rotating with the Sun. 17 April 1905