of Edinburgh, Session 1880-81. 
195 
In Table III. will be found the results of experiments on the 
oxidising effects of solutions of perchlorate, chlorate, and nitrate of 
potash acting on ferrous sulphate solution ( c ) for different lengths 
of time at ordinary temperatures. The mixture consisted in each 
case of 10 c.c. ferrous sulphate solution (c), 20 c.c. H 2 S0 4 , 30 c.c. 
water, and 10 c.c. of one of the oxidising solutions. 
Table III. 
Duration. 
Cub. 
cents. Permanganate. 
Chlorate 
decom- 
Temperature. 
Perchlorate. 
Chlorate. 
Nitrate. 
Blank. 
posed 
per cent. 
Hours. 
1 
° c 
18 to*19 
17*8 
12-5 
18-0 
18*0 
30-2 
23| 
14 to 19 
17*9 
2-25 
17*8 
17*8 
87 ’4 
51 
9 to 16 
17*7 
1*2 
17*8 
17*8 
93*2 
168 
9 to 18 
17*7 
0-3 
17*75 
17*75 
98*3 
From these results it will be seen that ferrous sulphate in sul- 
phuric acid solution, containing 0*1 gramme iron in 60 c.c. is stable 
at ordinary temperatures in presence of the quantity of nitrate or 
perchlorate of potash necessary for the complete oxidation of the 
iron. In the case of chlorate the oxidation goes on at such a rate 
that in one hour 30*2 per cent., and in seven days 98*3 per cent, of 
the iron has been oxidised. In connection with these experiments 
it was observed that a clear solution of bleaching powder saturated 
in the cold, oxidises ferrous sulphate at once and completely in the 
cold ; and that bromine water resembles chlorate of potash in re- 
quiring time, and being accelerated by a high temperature. 
The observations in Table IV. were made with a view to gain a 
closer insight into the behaviour of chlorate of potash solution at 
ordinary temperatures. The mixture exposed was in all cases 10 c.c. 
ferrous sulphate (c), 10 c.c. chlorate solution, 20 c.c. H 2 S0 4 , and 
30 c.c. water. In three blank experiments without chlorate 17*6 c.c. 
permanganate were used. 
