﻿ORGANIC MATTER IN AIR. 



17 



in simultaneous determinations on the same air, and are inlfluenced to 

 a marked degree by the quantity of air used. Another objection is the 

 difficulty with which the glass-wool is boiled with the permanganate on 

 account of the bumping and spirting that take place even though the 

 heat applied is barely sufficient to keep the fluid at the boiling point. 

 "With the utmost care possible several of the determinations of the dust- 

 form of organic matter were so vitiated from this cause as to necessitate 

 their omission from the table. 



For these different reasons I consider this to be a totally unreliable 

 and unsatisfactory method, and especially so with regard to the quanti- 

 tative determination of the relative proportions of organic matter in air 

 in its two forms, the gaseous and dust-form. In my hands it has failed 

 utterly to differentiate between these two forms of organic matter. 



Method III. 



Absorbent material : freshly ignited, finely granular pumice-stone. 



Absorption apparatus : a small glass tube, twenty centimetres in 

 length, consisting of a narrow portion four centimetres long .and three 

 millimetres in its internal diameter, and an expanded portion sixteen 

 centimetres long and twelve millimetres in its internal diameter, similar 

 in size and form to the absorption tube used by Kemsen and by Abbott 

 in their experiments. 



TABLE lY. 



No. of 

 experiment. 



Date, 1895. 



Amount of 

 air aspirated. 



Time 

 taken in 



Source of 

 the air. 



Mgs. of NHg in 1 cbm. of air. 





aspirat- 













ing. 





Free NH3. 



Alb. NH3. 



1 



6-III 



214.0 L 



3 hrs 



External 



2.3360 mgs 



9.3450 mgs 



2 



7-III 



386.0 " 



4 " 



(( 



7.7430 " 



1.2950 ' 





3 



7-III 



340.0 " 



H " 



(( 



1.4705 " 



4.4110 ' 





4 



8-III 



343.0 " 



34 " 



a 



1.4570 " 



2.9150 ' 





5 



8-III 



336.0 " 



3| " 



Room 



23.8095 " 



29.7610 * 





6 



9-III 



386.0 " 



4 - 



External 



10.5260 " 



13.1570 ' 





7 



ll-III 



393.0 " 



4 " 



(. 



10.1770 " 



12.7220 ' 





8 



12-III 



364.0 " 



3f " 



Room 



19.2300 " 



27.4720 ' 





9 



12-III 



295.0 " 



3 " 



External 



13.5590 '* 



84.7450 ' 





10 



13-111 



293.0 '' 



3 - 





0.0000 " 



102.3880 ' 





11 



13-111 



310.0 " 



3 " 



Room 



0.0000 " 



32.2580 ' 





12 



14-III 



370.0 " 



3f " 



External 



0.0000 '* 



10.8100 ' 





13 



14-III 



820.7 " 



4 " 



Sewer Pipe 



10.9660 '' 



8.5290 ' 





14 



15-III 



741.5 " 



3 " 





25.6230 " 



9.4400 ' 





15 



15-111 



300.0 " 



3 " 



External 



0.0000 " 



3.3333 ' 





16 



16-III 



1533.8 " 



5 " 



Sewer Pipe 



4.5660 " 



3.9111 * 





17 



16-III 



330.0 " 



H " 



Room 



12.1210 " 



9.0909 ' 





18 



16-III 



340.0 " 



3i " 



External 



1.4705 " 



1.4705 ' 





19 



18-III 



390.0 " 



4 " 



a 



0.0000 " 



5.1280 ' 





20 



18-111 



1075.4 " 



3i " 



Sewer Pipe 



21.8520 " 



13.4830 ' 





21 



19-III 



1971.1 " 



6f " 



(< 



6.0870 " 



4.5650 * 





22 



19-III 



556.0 " 



6f '* 



External 



0.9000 " 



3.5970 ' 





23 



20-III 



1282.5 " 



4i 



Sewer Pipe 



6.2380 " 



0.7799 " 



