[ 197 ] 



The air of the firft jar was exa-^ an ; f 

 amined at half an hour paft two in^SS 

 the afternoon; its teft was 2.o3; troyed 

 2.05I; 2.03I; 2.02; 2.54; 3.50. 450 



The air of the fecond jar was 

 examined between four and five 

 o'clock ; its teft was 2.06; 2.07^; 

 2.06; 2.02; 2.08; 3.03, 497 



The air of the third jar was ex- 

 amined between fix and feven ; its 

 teft was 2.i2{; 2.16^; 2. 14; 2.12; 

 2.56; 3.50. 55 o 



27. Three jars, of a gallon each, 

 full of pump- water, were expofed 

 at ten in the morning in the fun, 

 the weather being agreeably warm ; 

 each jar contained two handfuls of 

 the leaves of an Elm-tree. 



The air of the firft jar was put 



to the teft at two in the afternoon ; 



the refult was 1.90; 1.81; 1.76; 



2.66 ; 3.66. 337 



O 3 The 



