Royal Astronomical Society. 321 



' a-:? yy ROYAL ASTRONOMICAL SOCIETY, 'n li.ui ^S j70« ! ;, 

 ^ -m^hn^l [Continued from p. 149.] '^'<^^ ^^ ^j^^V^^^ 



May 9, 1S51. — Some Views respecting the Source of Lights &p. 

 By James Nasmyth, Esq., F.R.A.S. "' ^' 



" Impressed with the conviction that the progress of science has 

 often been most importantly advanced by the setting forth of hypo- 

 thetical views as to the nature of those causes which result in great 

 phsenomena, I am, for these reasons, induced to hazard and venture 

 forth with some views on the subject of the nature of solar light, 

 more especially in reference to the well-known but most remarkable 

 phsenomena, occurring in the case of stars of variable and transitory 

 brightness, as also in reference to those wonderful results of geolo- 

 gical research, namely, the unquestionable evidence of the existence 

 of an arctic or glacial climate in regions where such cannot now 

 naturally exist ; thus giving evidence of the existence of a condition 

 of climate, for the explanation of which we look in vain to any, a^ 

 present, known cause. '^ 



" I must plead the fact of the existence of such wonderful phae- 

 nomena as these alluded to as my apology for thus attempting to 

 come forth with what, although they may appear crude, theoretical 

 notions, yet may, as tending to direct increased attention to im- 

 portant phsenomena, so lead in due time to the development of 

 truth, and extend the present bounds of our knowledge of those 

 mighty laws which are so mysteriously indicated by the existence 

 of the phsenomena in question, and with the evidences of which we 

 are yet surrounded. j, 



** A course of observations on the solar spots, and on the remark- 

 able features which from time to time appear on the sun's surface, 

 which I have examined with considerable assiduity for several years, 

 had in the first place led me to entertain the following conclusion ; 

 namely, that whatever be the nature of solar light, its main source 

 appears to result from an action induced on the exterior surface of 

 the solar sphere, — a conclusion in which I doubt not all who have 

 attentively pursued observations on the structure of the sun's surface 

 will agree. ^ ^ , 



*' Impressed with the correctness of this conclusion, I was ledro 

 consider whether we might not reasonably consider the true source 

 of the latent element of light to reside, not in the solar orb, but in 

 space itself ; and that the grand function and duty of the sun was 

 to act as an agent for the bringing forth into vivid existence its due 

 portion of the illuminating or luciferous element, which element I 

 suppose to be diffused throughout the boundless regions of space, 

 and which in that case must be perfectly exhaustless. 



*' Assuming, therefore, that the sun's light is the result of some 

 peculiar action by which it brings forth into visible existence the 

 element of light, which I conceive to be latent in, and diffused 

 throughout, space, we have but to imagine the existence of a very 

 probable condition, namely, the unequal diffusion of this light- 

 yielding element, to catch a glimpse of a reason why our sun may, 

 in common with his solar brotherhood, in some portions of his vast 



