Referee's report by George Downing Liveing and Arthur William Rucker, on five papers 'On the chief line in the spectrum of the nebulae', 'Note on the spectrum of the nebula of orion' and 'Preliminary note on photographs of the spectrum of the nebula in Orion' by Joseph Norman Lockyer, 'On a re-determination of the principal line in the spectrum of the nebula in Orion, and on the character of the line' and 'Note on the photographic spectrum of the great nebula in Orion' by William Huggins Recommended for publication in the Proceedings of the Royal Society of London. The papers are not carefully referenced, and some argument could be omitted. Refers to work by Lieutenant Bacon. The matter could be solved by friendly cooperation between the two authors. The invitation to inpsect the apparatus extended to William Huggins by Joseph Norman Lockyer, which was turned down, should be stated. 'There appears to us to be room for a reasonable difference of opinion on this point and we think thus far that Mr Lockyer should be allowed to express his view'. The nature of the notes provided by William Huggins made the process of understanding them difficult. It should be made clear that in cases of disagreement such as this, all notes should be made available to both parties. Subject: Astronomy [All papers published in the 'Proceedings of the Royal Society of London', 1891] 27 May 1890