﻿OEGANIC MATTER IN AIR. 



25 



filter. It will be noted that in each instance the free ammonia is 

 lower with than without the dust-filter, and only in two instances is 

 the albuminoid ammonia lower without than with the use of the dust- 

 filter. The total ammonia is, however, constantly lower with than 

 without the use of the dust-filter, so that there is strong evidence that 

 the dust in the air is the source of a large part, if not all, of the 

 organic matter. It is probable that the dust-filter of asbestos failed 

 to filter out the finer dust particles, and it is from these we still get 

 the reaction of ammonia in these determinations with the use of the 

 dust-filter. 



TABLE XV. 



No. of 



Date, 



experi- 

 ment. 



1895. 



1 



15-X 



2 



15-X 



3 



16-X 



4 



16-X 



5 



21-X 



6 



21-X 





1896. 



7 



12-III 



8 



12-III 



9 



12-III 



10 



12-III 



11 



12-III 



12 



12-III 



13 



12-III 



14 



13-III 



15 



13-III 



16 



18-III 



17 



13-III 



18 



13-III 



19 



13-III 



20 



13-III 



Amount of 

 air used. 



7.25 

 192.0 

 8.0 



8.0 

 7.5 

 7.25 



41.0 



38.7 



15.75 



14.1 

 3.775 

 3.83 

 3.754 

 3.775 

 3.83 

 3.754 



38.0 



82.9 

 7.85 

 7.75 











Mgs. of NH3 in 1 



Time 

 taken 



Source 

 of the 



With or 





cbm. of air. 







Method. 







rating. 



air. 



dust-filter. 





FreeNHa 



Alb. NH3 











mgs. 



mgs. 



4f h. 



Room 



Without 



I-a 



0.0052 



0.0317 



4f " 



(( 



(( 



Ill-a 



0.3448 



0.6896 



4f " 



'( 



u 



I-a 



0.1250 



0.7625 



4f " 



" 



(( 



Ill-a 



0.0625 



0.5000 



6 - 



(( 



(( 



I-a 



0.0666 



0.0133 



6 " 



(( 



ii 



Ill-a 



0.0000 



0.0000 



6f- 



(( 



With 



Ill-a 



0.0000 



0.0268 



6f " 



(( 



Without 



Ill-a 



0.0129 



0.0516 



6|" 



" 



With 



I-a 



0.0000 



0.0666 



6f " 





Without 



I-a 

 IV-a 

 IV-a 

 IV-b 

 IV-a 

 IV-a 

 IV-b 



0.0000 



0.0422 



6 " 



(( 



With 



Ill-a 



0.0000 



0.1184 



6 " 



" 



Without 



Ill-a 



0.0240 



0.0904 



6 " 



" 



With 



I-a 



0.0000 



1.0191 



6 " 



a 



Without 



I-a 



0.0000 



1.2903 



Mgs. of 

 O con- 

 sumed 

 fori cbm, 



mgs. 



3.1788 

 3.1331 

 2.6638 

 8.4765 

 8.3550 

 4.2621 



The results in this table seem to indicate that the amount of organic 

 matter, as shown by Methods lY-a and b, bears some relation to the 

 amount of ammonia as shown by Methods I and III. The results ob- 

 tained with Method III are lower as a rule than those obtained with 

 Method I. The influence of the dust-filter on the quantity of organic 

 matter recovered from the absorbent material is most marked with 

 Method III. 



CONCLUSIONS. 



1. The quantity of organic matter bears an intimate relation to the 

 amount of dust floating in the air. It is probable that the gaseous 



