and Astronomical Notices. 183f 



in this direction Iiaving been recently communicated by Mr 

 James Nasmyth, C.E., to the Astronomical Society of London, 

 they may be interesting to our readers, and in his own 

 words. 



*' Impressed with the conviction that the progress of science 

 has often been most importantly advanced by the setting 

 forth of hypothetical views as to the nature of those causes 

 which result in great phenomena, 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 refer- 

 ence to the well-known but most remarkable phenomena, 

 occurring in the case of stars of variable and transitory 

 brightness, as also in reference to those wonderful results of 

 geological 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, at present, known cause. 



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

 phenomena as these alluded to as my apology for thus 

 attempting to come forth with what, although they may ap; 

 pear crude, theoretical notions, yet may, as tending to direct 

 increased attention to important phenomena, 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 phenomena in 

 question, and with the evidences of which we are yet sur- 

 rounded. 



" A course of observations on the solar spots, and on the 

 remarkable features which from time to time appear on the 

 sun's surface, which I have examined with considerable assi- 

 duity for several years, had in the first place led me to enter- 

 tain 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 



