672 



MR JOHN AITKEN ON THE NUMBER OF DUST PARTICLES IN THE 



Table I. — The Number of Dust Particles in the Atmosphere for 1891 — continued. 









O w 





rt 



_tj> 







Place. 



Date. 



Hour. 



Number 

 Partich 

 per c.c 



Wind. 



!g 



S3 



"a 

 w 



State of 

 the Air. 



Remarks. 





July 

















KlNGAIRLOCH . 



21 



1 P.M. 



625 



S.E. 1 



61-5 



5 



Thickish 



Cloud \, carry S.W.; 

 clouds low. 







4 P.M. 



1,475 



S.E. 0-2 



63-5 



7-5 



Clear 









7 P.M. 



2,400 



N.E. 0-1 



59 



4-7 



jj 



Cloud J. 







9 P.M. 



1,475 



N.W. 0-2 



53-3 



2-3 



Medium 





)> 



22 



10 A.M. 



574 



N.W. 0-5 



55-5 



1-5 



Clear 



Cloud \, carry N.W.; 

 showers. 







1 P.M. 



677 



N.W. 3 



58-3 



43 



jj 



Cloud \, carry N.W. 







5 P.M. 



381 



J) 



56 



3 



jj 



Cloud i, carry N.W.; 

 a few drops of rain. 







9 P.M. 



280 



N.W. 1 



54 



2 



jj 



Cloud T V 



JJ 



23 



10 A.M. 



241 



)> 



58 



4 



jj 



Cloud £, carry N. 







1 P.M. 



364 



N.W. 2 



60-5 



5-5 



jj 



jj 







1.30 P.M. 



550 



n 



5) 



>) 



jj 



u 







4 P.M. 



3,600 



N.W. 1 



63 



7-2 



jj 



Clouds very thin. 







5.30 p.m. 



3,150 



N.W. 0-5 



58-5 



5 



Very clear 



Cloud 1, very thin, carry 

 N.W. 







8 P.M. 



3,350 



N.W. 0-2 



55 



4 



Medium 



Cloud ~ ; a few drops of 

 rain. 



JJ 



24 



9 A.M. 



238 



N.W. 0-5 



56-5 



4-5 



Medium 



Cloud i, carry W. 







10 A.M. 



251 



N.W. 1 



58 



4 



Thickish 



Cloud \, carry W.; a 

 few drops of rain. 







1 P.M. 



106 



N.W. 3 



57 



4 5 



Clear 



Cloud i, carry W. 







1.30 P.M. 



469 



N.W. 2 



57-2 



5-2 



JJ 



Cloud i carry N.W.; 

 a few drops of rain. 







6 P.M. 



606 



N.W. 1 



55 



4 



JJ 



Cloud i. 







8.30 p.m. 



297 



•)•) 



53-5 



3 



Thickish 



jj 



J> 



25 



10 A.M. 



205 



N.W. 2 



58 



5 



Medium 



Cloud |, carry N.W.; 

 clouds low. 







1 P.M. 



123 



N.AV. 1 



57-5 



4-1 



jj 



Cloud \ ; a few drops 

 of rain. 







4 P.M. 



371 



JJ 



57 



4 



>j 



jj jj 







7 P.M. 



234 



JJ 



57-2 



4-2 



jj 



Cloud \, carry W. 







9 P.M. 



105 



JJ 



54-4 



2-4 



Clear 



Cloud i ; very clear 

 between showers. 



JJ 



26 



10 A.M. 



47 



N.W. 1 



59-4 



2 



jj 



jj jj 







1 P.M. 



43 



N.W. 2 



64 



4 



u 



Cloud f, carry S.W.; 

 showers. 







1.30 P.M. 



43 



JJ 



62-7 



3-7 



Extremely 

 clear 









4 P.M. 



760 



N.W. 1 



58-7 



3-5 



Clear 



Cloud i, carry S.W.; 

 clouds low. 







7 P.M. 



214 



JJ 



57 



2-5 



jj 



Cloud -] , carry W. 







9 P.M. 



132 



JJ 



56 



2-4 



jj 



jj u 



JJ 



27 



10 A.M. 



526 



N.W. 3 



54 



6 



Very clear 



Cloud .'„ carry N.N.W. 







11.30 A.M. 



2,000 



JJ 



56-4 



7-4 



jj 



Cloud |, carry N.W. 







1 P.M. 



1,000 



JJ 



56 



6 



jj 



jj jj 







3 P.M. 



559 



JJ 



53-5 



5-2 



jj 



Cloud J, carry N.W. 







5.30 p.m. 



753 



JJ 



54 



5 



j) 









7 P.M. 



1,800 



JJ 



52 



1 



Thickish 



Cloud ], carry N.W.; 

 slight showers. 







9 P.M. 



562 



JJ 



51 



3 



Medium 



Cloud i, carry N.W. 



)) 



28 



10 A.M. 



123 



JJ 



54-5 



5-5 



Extremely 

 clear 



Cloud |, carry N.W. 



