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No. 3. Mr. J. Fife to Mr. W. Seed. Young's Paraffin Light and Mineral Oil Company (Limited), General Manager's Office, 13, Dundas Street, Glasgow, 29th May, 1876. Sir, — Lighthouse Oil. Referring to my letter of 16th March, 1 beg to send herewith six prints of report on our lighthouse oil obtained from Dr. Stevenson Macadam, one of the foremost chemists in Great Britain, particularly in regard to hydrocarbons. He is besides Chemical Adviser to the Northern Lighthouse Commissioners, who have charge of all the lighthouses in Scotland, and has devoted more attention to the study of suitable oils and lamps for lighthouses than I believe any other chemist in the United Kingdom. I asked for this report from him solely in consequence of your letter to me, and I trust that it will enable us to remove the shippers' objections to the transit of an oil so thoroughly safe. "We will endeavour to accomplish what we can at this end. I have, &c, John Fife, W. Seed, Esq., Secretary of Customs (Marine Branch), General Manager. Wellington, New Zealand. Young's Pabaffin Light and Mineral Oil Company (Limited). Foreign Lighthouse Oil. Analytical Laboratory, Surgeons' Hall, Edinburgh 25th April, 1876. I HAVe to certify that I have carefully analyzed and tested a sample of foreign lighthouse oil, forwarded to me by Young's Paraffin Light and Mineral Oil Company, with the special object of determining the relative safety of the oil as compared with the other paraffin oils, and of estimating the relative photogenic or illuminating value of the oil as contrasted with the ordinary colza burning oil. The foreign lighthouse oil under examination was a clear, almost colourless, paraffin oil, with the specific gravity of 816 (water = 1000), a flashing point of 165° F., and a firing point of 178° F. The oil is, therefore, a very safe one, and shippers and steamboat proprietors may confidently carry it without the risk of explosion or fire. It possesses the highest flashing and firing points of any clear burning paraffin oil which I have met with. In the determination of the illumiuating value of the oil, I employed two sizes of the Doty lighthouse argand lamp for the consumption of the oil, viz. the one inch wick lamp, and the one and oneeighth wick lamp. The photogenic results were contrasted with the light evolved from the one inch argaud lamp consuming colza oil, and the following experimental data were obtained : — Relative Photogenic or Illuminating Power of the Light evolved during the Combustion of the Foreign Lighthouse Oil in the Doty Lighthouse Lamps, and of Colza Oil in the Lighthouse Argand Colza Lamp.

Foeeigk Lighthouse Pabaffin Oil. Colza Oil. Doty 1-inch Argand. Doty lj-inch Argand. 1-inch Argand. A. Consumpt. of oil per hour, by weight ... Consumpt. of oil per hour, by volume in ounces ... Consumpt. of oil'per hour, by volume in gallon ... 1-626 ounces. 1-993 ounces. 1-923 ounces. 2-357 ounces. 1-950 ounces. 2133 ounces. B. Photogenic or illuminating power of the light evolved during the combustion of the oil in the respective lamps, determined by Bunser's Photometer, and calculated into standard sperm candles, each consuming 120 grains of sperm per hour ... 0-0124 gallon. 0-0147 gallon. 0-0133 gallon. 19-78 candles. 23-55 candles. 11-33 candles. C. Total value of the light obtained from the combustion of one gallon of the oils in the respective lamps, calculated from the candle power, and given in pounds of sperm candles ... 27346 lbs. 27-463 lbs. 14-603 lbs. D. Relative photogenic or illuminating value in candle power of the foreign lighthouse oil in the Doty lamps, taking the colza oil in the argand lamp as standard or unity, l'OOO ... 1-746 2-079 1-000 E. Belative amount of total light evolved from one gallon of the respective oils, calculated from the pounds of sperm (c), and taking colza oil as standard or unity, 1000 1-872 1-881 1000