240 Dr Richardson's Observations on Solar Badiation, 



cility he had in preparing articles like those of which I have 

 spoken. He says, " I was obliged when at school to make 

 out a sketch of the sermons we heard in church. This prac- 

 tice afterwards proved of great benefit to me in reading, ex- 

 tracting, and reviewing/and in the performance of many public 

 duties, because it gave me the power of selecting, retaining, 

 and expressing concisely the essential points under consider- 

 ation." 



As Blumenbach was involved in few literary feuds, it did 

 not easily happen that his critiques drew down upon him 

 hatred or anger; but sometimes he could not avoid calling things 

 by their proper names, and exhibiting false celebrity in its 

 real nakedness.* 



(To be concluded in our next Number. J 



Observations on Solar Badiation, made at Fort Franklin in the 

 years 1825, 1826, and 1827. By John Richardson, MX)., 

 F.R.S., and Inspector of Naval Hospitals. Communicated 

 by the Author. 



While residing at Fort Franklin, in North America, in the 

 year 1825-26, 1 made a series of observations on the heating 

 power of the sun's rays with a black-bulb thermometer, and 

 some of the results were published in the " Appendix to the 

 Narrative of Sir John Franklin's Second Journey." It has 

 been observed by an eminent philosopher, in reference to ob- 

 servations of this kind, that, as measures of solar radiation, 

 they have generally been made on an erroneous principle, 

 " the true indication of the force of the solar rays not being 

 the statical effect upon the thermometer, but their momen- 

 tary intensity, measured by the velocity with which they com- 

 municate heat to an absorbent body."f The actinometer has 



* His critique of KanipPs New Method of curing the most obstinate Diseases 

 of the Bowels (Med. Bibl. vol. ii. No. i.) gave offence to the author, but yet- 

 afterwards obtained from him for Blumenbach public thanks (in the second 

 edition of that book, Leipsic, 1786, p. 3CC). 



t Sir John Herschel, quoted in the Report by Professor Forbes on Me- 

 teorology ; Trans, of the British Association, vol. i. 



