Referee's report by Richard Tetley Glazebrook, on a paper 'The optical properties of vitreous silica' by J W Gifford and William Ashwell Shenstone Sectional Committee: Physics and Chemistry Recommended for publication, but is doubtful as to whether Philosophical Transactions or Proceedings are the proper mechanism for publication. The results are important and should be given in detail. He has no modifications of importance to suggest. All the illustrations should be reproduced. No general remarks are given. [Published in Proceedings of the Royal Society, 1904]. Endorsed on verso as received 1 February 1904. 30 January 1904