Correspondence between members of the Railway Gauge Commission and the general public concerning the commission. The papers include statistics of the railways, plans and measures of the engines, manuscript and printed recommendations of the Commission, and extracts from newspaper articles.

Correspondence between the Railway Gauge Commission and the railway companies, including manuscripts to supplement the interviews and miscellaneous papers on experiments between broad and narrow gauges and other subjects.

A volume concerning the gauge question titled 'Gauge Evidence. The History and Prospects of the Railway System, illustrated by the evidence given before the Gauge Commission. By Samuel Sidney'.

Minutes of interviews held by the Railway Gauge Commission, 6 August - 4 September 1845. The interviewees are R. Stephenson, J. Locke, J.E. McConnell, Col. G. Landmann, H. Pringle, M. Bruyeres, A. Martin, W. Cubitt, Captain J. Milligan Laws, T.J. Buckton and J. Gray.

Minutes of interviews held by the Railway Gauge Commission, 17-30 October 1845. The interviewees are D. Gooch, S. Clarke, C.A. Saunders, I.K. Brunel, W. Fernihough, W. Harding and B.W. Horne.

Minutes of interviews held by the Railway Gauge Commission 1 November - 18 December 1845. The interviewees are T. Whitaker, J. Sanders, I.K. Brunel, W. Bass, E. Wood, N. Wood, R. Down, G. Hudson, T. Jackson and Major General C.W. Pasley.

Printed minutes of the Railway Gauge Commission interviews corrected by the interviewees who appear in RGO 6/285-287. Other interviewees are C.B. Vignoles, J.U. Rastrick, E. Bury, J. Braithwaite, Captain W. O'Brien, T.C. Mills, G. Rodmer, Captain M. Huish, E. Jones, R. Creed, P. Clarke, J. Brown, R. Roberts, W.J. Chaplin, J. Hawkshaw, J. Ellis, J. Hayward, J.P. Budd, General Sir J.W. Gordon and Major Sir J.F. Burgoyne.

Proof sheets of the minutes of interviews held by the Railway Gauge Commission, including some duplicates. The latter portion has been revised by Sir F. Smith and others appear to have been corrected by the interviewees.

Printed minutes of interviews held by the Railway Gauge Commission, with an appendix.

Letters received by the Secretary of the Railway Gauge Commission relating to the formation of the Commission, the return of completed circulars, and the date and time of appointments for interviews. There are letters from G. Stephenson, J. Saunders, I.K. Brunel, J. Nasmyth, W. Cubitt, R. Stephenson and others. There is also an extract from Bradshaw's 'Railway Gazette' and other newspapers.

Minutes of the Railway Gauge Commission, 18 July - 2 December 1845. At the back of the volume are copies of letters sent out by the Commissioners for the collection of materials and interviewees for its report.

An official paper titled 'Supplemental Observations on the published evidence and appendix of the Gauge Commission'.

A booklet titled 'Observations on the Report of the Gauge Commissioners as presented to Parliament'.

An official paper presented to Parliament titled 'Observations on the Report of the Gauge Commissioners'.

Replies from the railway companies to circulars sent out by the Railway Gauge Commission asking for particulars.