SIR HALLEY STEWART, whose death at the advanced age of ninety-nine years occurred on January 26, was a generous supporter of scientific research. One of his outstanding benefactions was the founding of the Halley Stewart Laboratories for Physics Research at Hampstead, which now forms a post-graduate school of the Physics Department of King's College, London. These laboratories were in the first instance put at the disposal of the College in 1932 for the special use of Prof. E. V. Appleton, whose radio researches in the college buildings in the Strand had been greatly hampered by the electrical interference caused by adjacent machinery. The premises in Hampstead, which were formally opened by Lord Rutherford, provided a fully equipped electrical research laboratory as well as a residence above, for the professor of physics. During the years 1932-36, Prof. Appleton and his students were able to continue unhampered their exploration of the properties of the higher atmosphere using radio waves emitted from the roof of King's College and received at Hampstead. Since Prof. Appleton's translation last year to Cambridge, the Halley Stewart Laboratories have been directed by the present Wheatstone professor, Dr. C. D. Ellis, whose researches lie mainly in the field of radioactivity.