973 
curve of viscosity will still give any information about these hydrates 
at 15°. 
Also with a view to this the concentrations were examined between 
61 and 83 weight °/, SO, 
The investigation was carried out at three different temperatures, 
viz. 15°, 40°, and 60° with the following result: 
weight 0/0 Time of outflow Time of outflow | Time of outflow 
SO, at 15° at 40° | at 60° 
88,84 5 min. 21/5 sec. 2 min. 21!/s sec. | 1 min. 2045 sec. 
82,13 | ZN 10 ME ay ISHS 
81,72 Per bn | 
81,55 ae ae, Den We Re | eee 
81,42 te ae 
80,53 ate weit ot AEN Sioa whe eee ee 
17,55 pe ain ode zijnde 
16,27 Amen lk 
15,12 A panies EE 
15,33 EERE, 
75,19 A= tat 
15,03 hrm er bom 1s. x 
73,96 [neg dT ie bena loes. 
12,69 ET ee ee 
12,08 Re 
69,72 Dee fc eae ee 
69,60 i Sana’ tebe 
64,78 eenden Sr. ie den 
63,76 gS Se 
63,28 | 1, > 90 » 59'/5 „ 
Fig. 3 represents these results graphically. It shows that the curve 
of viscosity at 15° really has the same shape as that of the system 
H,O—Fe,Cl, at 40°. The curves found at 40° and 60° show further 
that the peculiar character of the shape of the curve of viscosity 
