Folder containing: a three page letter on the equation of time (letter about GMT images); a letter regarding sextant readings by J. Bolam; a paper on calculating the distance of the horizon and to land at sea; a paper on solving astronomical problems, namely the difference between watch and dial and how to find latitude and longitude, undated; a paper on the true bearings of the sun at Ochtertyre, Stirling, undated [there was a private observatory at Ochtertyre built by Sir William Keith Murray in 1852]; sheets of papers with calculations relating to ϴ Capricori, Oct 1878; papers with prediction for the reappearance of Venus on the GERMANIE between New York and Liverpool in August 1878 (2 sheets); two loose sheets of calculations; a sheet of notes and calculations on headed notepaper from Ochtertyre, Stirling.

Administrative / biographical background
Colin Dundas (1842-1911) joined the navy as a cadet in 1855. He served on the TOPAZE as Lieutenant between January 1866 and September 1869. He was promoted to Commander in 1877 and retired in 1882.