[ ^91 ] 



refult by ~-|^-' ^ difference which evidently arifes partly from the 

 efcape of the red vapours and partly from want of fufficient time 

 for penetration ; it fhould however be remarked, that in large vef- 

 fels there may fometimes be an increafe of weight from the ab- 

 forption of oxygen by the nitrous air expelled by the generated 

 heat. 



'Experiment i^h. 



Mr. Richter (Stochymctrie, 3 theile, p. 9.) mixed fpirit of 

 nitre, whofe fp. grav. was 1,5304 with water, in the proportion of 

 100 parts of the acid with 342 of water, and found the fp. grav. 

 of the mixture 1,123 J ^^^^ temperature is not mentioned. 



Application. 



100 grains nitrous acid 1,530 contains by my tabic about 70 

 grains real acid, and when mixed with 342 of water, 442 grains 

 will then contain 70 real acid, and confequently 100 grains of the 

 mixture will contain 15,83 of real acid, this quantity lies between 

 the tabular acidities 16,17, and 15,44, and by the 2d problem it 

 will be found to correfpond with the fp. grav. 1,120. 



Gf 



