Report of the Meetings for 1895. 217 



Dr Stevenson Macadam, Edinburgh, briefly explained to 

 the visitors how paraffin oil came to be used in this and 

 other lighthouses as an illuminant. St. Abbs, he said, was 

 one of the lighthouses selected for the purpose of testing 

 how far paraffin oil could be used with safety. Grave 

 doubts had been cast upon the possible use of paraffin, 

 owing to the explosive character of various sorts ; but after 

 experiments, which he conducted under the instructions of 

 the Commissioners of Northern Lighthouses, it was proved 

 that the oil could be employed witli safety, and with 

 manifest advantage of the public. In fact, although paraffin 

 was at the time very much dearer than it is now, yet its 

 introduction into the lighthouses showed that, for one half 

 of the price paid for colza oil, the previous illuminant, a 

 better light could be obtained. As the result, paraffin was 

 universally introduced into the N(jrthern Lights, and also 

 into the Southern Lights, excejjt in a few cases where gas 

 or electric light was used. 



To show the care with which the oil was selected, the 

 Government, while allowing an oil to be sold for domestic 

 purposes with a flashing point of 73 degrees Fahrenheit, the 

 Northern Lighthouse Gommissinners had always insisted on 

 having a much safer illuminant, and for many years an oil 

 had bef^n employed with a flashing point of 140 degrees 

 Fafi. The highest temperature observed in a lighthouse, 

 under actual experiment, was 85 degrees Fah. ; and thus 

 there was an absolute margin of safety between the tempera- 

 ture of the lighthouse and the flashing point of the oil of 

 50 degrees Fah. 



Mr Morton, Sunderland, Inspector of Lighthouses, said 

 that, within the memory of middle-aged men, the Government 

 was paying 6s. 8d. per gallon for spermaceti oil for use in 

 the lighthouses ; and, when at that price, considerable 

 anxiety was evinced in consequence of a probable extermina- 

 tion of the whales from which the oil was obtained. This 

 illuminant was superseded by colza oil — extracted from rape 

 seed lar2:ely grown in France — at a cost of 3s. per gallon. 

 That agam had given place to mineral oil, as they had 

 been told, at a price not exceeding perhaps one fifth of 

 the cost of colza oil, and with a much greater illuminating 

 power. 



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