a new Eudiometer, 1 3 j- 
ceived by the nitrous teft, and that in moft rooms the air is fo 
frequently changed, that a conliderable quantity of phlogifti- 
cating materials may be kept in them without fenfibly impair- 
ing the air. But it muft be obferved, that the nitrous teffc 
fhews the degree of phlogiftication of air, and that only ; 
whereas our fenfe of fmelling cannot be conhdered as any teft 
of its phlogiftication, as there are many ways of phlogifti- 
cating air without imparting much fmell to it; and, 1 believe, 
there are many ftrong fmelling fubftances which do not fenfibly 
phlogifticate it.. 
I 
