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1. Observations on the Annular Solar Eclipse which occurred 

 on the 15th of Mai/ 1836, by William Galbraith, Esq. 

 2. Observations on the Eclipse, by Commander Alexander 

 Milne. 3. Observations made with LesUe'^s Photometer 

 during the Eclipse, by E. Sang, Esq. 



An eclipse of the sun, it is well known, is caused by the 

 body of the moon coming between the spectator on the earth''s 

 surface and the sun, thereby producing a greater or less de- 

 gree of darkness according to the magnitude of the eclipse. 



In the early ages of the world, men were either ignorant of, 

 or at least not well acquainted with, the natural causes on 

 which these phenomena depend ; and consequently they were 

 then regarded with superstitious awe, but now they are hailed 

 with satisfaction as phenomena highly valuable for the pur- 

 pose of improving our knowledge of astronomy, geography, 

 and navigation. On this account some of our most zealous 

 practical astronomers travelled hundreds of miles in order to 

 observe this eclipse to the greatest advantage. 



Those observers here who felt an interest in these depart- 

 ments of science, continued for some time previously to pre- 

 pare to observe it as effectively as their circumstances would 

 permit ; and in several instances within our knowledge this 

 was satisfactorily performed, and the agreement in the results 

 almost as close as could reasonably be expected. 



Throughout Europe the same vigilance will doubtless be 

 manifested, from which a mass of observations must be ob- 

 tained that will at this epoch fix with extreme precision the er- 

 rors of the lunar tables which have already attained so high a 

 degree of accuracy, by the labours of those astronomers and 

 mathematicians who have done so much for the advancement 

 of their favourite science. 



My observations were made within the grounds of the obser- 

 vatory of Edinburgh on the Calton Hill, in Lat. BS"" 57 22'\5 N., 

 Long. 12"^ 43^5 W., as deduced from previous observa- 

 tions ; and these I believe to be within the limits of admissible 

 errors inseparable from observations. The instruments used 

 were an inverting telescope, magnifying about fifty times, and a 



