34 



DR. R. ANGUS SMITH ON THE 



he found a decrease on June 20th during a violent wind, 

 probably from the same cause, namely mixing. 



De Luna has lately examined the air of Madrid, with the 

 following results* : — 



Air of Madrid, outside the walls, during month of March. 



(ist series.) 



Place. 



Oxygen. 



Carbonic acid 

 per cent. 



1 



2 



3 



4 



5 



6 



7 



8 



9 



10 



11 



12 



2071 

 2079 

 2077 

 2077 

 2073 

 2075 

 2070 

 2074 

 2o'69 



20-8 I 



2079 

 2078 



0-05 

 003 

 0-03 

 0*05 

 o'o6 

 0*03 

 o'o6 

 0*05 

 0*09 



0*02 



0*03 

 0*04 



Air of Madrid, within the walls, during month of April. 

 (2nd series.) 



Place. 



Oxygen. 



Carbonic acid. 



1 



2070 



o'o6 



2 



2070 



o'o6 



3 



2077 



0*03 



4 



2075 



o'o5 



5 



2070 



o-o6 



6 



20*69 



o-o6 



7 



2078 



0-05 



8 



20"69 



o'o8 



9 



2070 



o*o6 



10 



2078 



0*04 



II 



2o-8o 



0*03 



12 



2073 



0*04 



The amounts of oxygen are very small, and of carbonic 

 acid very high. Solutions were used for the oxygen, and 

 permanganate of potash for the organic matter. 



* Estudios Quimicos sobre el aire atmosferico de Madrid, por D. Eamon 

 Torres Munoz de Luna. Madrid, i860. 



