260 Population of Russia. [April, 



incidence 54° 35' its light will have the greatest intensity. Beyond 

 that limit it begins again to disappear. This phenomenon proceeds 

 from this circumstance, that the light transmitted obliquely loses by- 

 polarization the faculty of being reflected. 



I do not consider the knowledge of these phenomena as more 

 favourable to the system of emission than to that of undulations. 

 It demonstrates equally the insufficiency of the two hypotheses. In 

 fact, how can we explain either by the one or the other why a 

 polarized ray can pass totally at a certain inclination through a 

 diaphanous body without experiencing that partial reflection which 

 takes place at the surface of bodies in ordinary cases ? 



It remains for me to thank you for the eriometer which you were 

 so good as to send along with your letter, by means of which we 

 may judge of the fineness of different wools and other very small 

 bodies. It is a very useful application of the laws which you have 

 deduced from your ingenious hypothesis respecting the combined 

 movements of light, and a new proof of the advantages which the 

 arts derive from the progress of the sciences. 



I request you to present to the Royal Society one of the copies of 

 the Theory of Double Refraction which accompany this letter, and 

 to accept the other as a raaik of my particular esteem. 

 1 have the honour to be. Sir, 



VVith the greatest respect, 



Your most humble and obedient servant, 

 Malus, 

 Member of the Imperial Institute 

 of France. 



Article IV. 



On the Number of Inhalitants in Russia, and on the Progress of its 

 Population, accmding to the Statements made by order of Go- 

 vernment. By C. T. Hermann. 



( Concluded from p. 1 73. ) 



Part II. 



Of the -Progress of Population in Russia. 



Ths Rrst revision of 1/22 gave 5,794,928 males, which, sup- 

 posing an equal number of women, makes a population of 

 11,589,856 individuals. How much ought we to add for the nevf 

 acquisitions in which the revision did not take place ? 



An enumeration made in Little Russia* in 176S gave 955,228 

 inhabitants; another, made in Finland in 1755, gave 117,998. 

 Esthland, in 1773, had 176,000; Livonia, 447,360. All these 



♦ Hermann, Journal Statistique, t. i. partie ii. p. 14. 



