RAI Sahib Professor Ruchi Ram Sahni, M.A., has, we learn, received an extension of leave till the 15th December next, though it will rest with him to avail of the whole or a portion of it as he may find it necessary for his purpose. This will enable him to devote himself for some months longer to the special research work upon which he is engaged in the Physics Laboratory at Manchester. He contributed to the June number of the Philosophic Magazine the result of his researches on "The Photographic Action of Alpha, Beta and Gama rays" for which he had to prepare a large number of photographs. It is gratifying to learn that the Rai Sahib's work has, on this very technical subject, been warmly received by those competent to judge of it. He is now engaged on a second paper which, it is hoped, will prove no less useful than the first.