188 
DR. GLADSTONE ON CIRCUMSTANCES MODIFYING 
which may evidently be reduced to a unity of F by dividing by x, thus- 
F+-K=^. 
' X X 
On this principle the experiment may be thus tabulated: — 
„ . ^ Sulphocyan. of 
Feme nitrate. potassium. 
Red salt 
produced. 
Ferric nitrate. Sulphocpn. of 
potassium. 
Red salt 
produced. 
1 equiv. -1-3 equivs. 
1 equiv. -f- 1*5 equiv. 
1 equiv. -f 1 equiv. 
1 equiv. -1- 0*75 equiv. 
88 
55-25 
40-66 
32-75 
1 equiv. -1-0-6 equiv. 
1 equiv.-)- 0-5 equiv. 
1 equiv. -f 0-3 equiv. 
1 equiv. -1-0-21 equiv. 
27-6 
24 
16-1 
12-43 
which numbers are represented by the broken line in Plate VIII. fig. 1. 
It need scarcely be explained, that had the whole of the sulphocyanogen present 
in the above experiment united itself with the iron, the second term would have 
indicated 44 degrees instead of 55 25 , the third 29*33, and so on ; and the diagram 
would have presented a straight line joining 0X0 and 3x88 ; while no excess of 
sulphocyanide would cause the line to sink below 88. 
In order to confirm, by a more direct experiment, the result just arrived at, two 
mixtures were made, each consisting of 100 gr. meas. of ferric nitrate, and 2 gr. meas. 
of sulphocyanide of potassium ; that is, one equiv. of the former to 0*24 equiv. of the 
latter. The experiment was conducted precisely as in the previous cases, additional 
quantities of the sulphocyanide being mixed with one of the red solutions. The 
results form the subjoined Table. The comparative amount of red salt produced is 
given in two columns : in the first 88 is taken as the starting-point (which was the 
case in the actual experiment), in the second 88 is assumed as the expression of the 
amount produced when one equiv. of ferric salt is mixed with three of the sulpho- 
cyanide, and the numbers are calculated accordingly, so that this column should tally 
with those of the previous experiments. 
Ferric nitrate. S^lphocpn. of 
potassium. 
Red salt 
produced. 
Ferric nitrate Sulphocyan. of 
c nitiate. potassium. 
Red salt 
produced. 
1 equiv.-)- 0-24 equiv. 
1 equiv.-)- 0-48 equiv. 
1 equiv. -f 0-78 equiv. 
1 equiv.+ l-05 equiv. 
1 equiv.-)- 1-31 equiv. 
1 equiv.-f 1-83 equiv. 
1 equiv. -1-2-22 equivs. 
1 equiv.-)- 2-88 equivs. 
88 
138 
183 
226 
279 
320 
355 
400 
19 
29*7 
39-4 
48-7 
60-2 
69 
76-5 
86-3 
1 equiv.-)- 3-57 equivs. 
1 equiv.-)- 4-44 equivs. 
1 equiv.-f 5-58 equivs. 
1 equiv.-f 7'08 equivs. 
1 equiv.-f 8-64 equivs. 
1 equiv.-f 10-29 equivs. 
1 equiv.-f 11-79 equivs. 
450 
502 
552 
623 
683 
733 
778 
97-8 
108-2 
119 
134-3 
147-3 
158-1 
167'8 
These numbers form the long curve projected in Plate VIII. fig. 1. The dotted line 
is that of the previous experiment (vide above), showing an almost perfect agree- 
ment. The broken line seems to follow the more continuous course. Where the 
sulpliocyanide was not in excess, there appears a slight discrepancy between the two 
experiments. 
