326 I^IE. G. GOEE ON THE PEOPEETIES OE ELECTEO-DEPOSITED ANTIMONY. 
exceeding 1 grain per square inch per hour. The exact proportion or strength of the 
ingredients is not important, provided the acid is not too concentrated, sufficient oxide 
is dissolved in it, and the electric current is very feeble. 
104. The deposit is generally at first scaly, especially if the voltaic current is rather 
strong ; but afterwards it is dull in appearance and grey like that formed in the bromide 
solution, and the tendency to the evolution of gas is much greater than in that liquid. 
It is also liable to cohesive action and crackling (17. 94.), but in a less degree than the 
other kinds. Its cohesion is very feeble, and it is much more friable than the bromide 
variety ; its fractured surface is dull and earthy in appearance, and it has a much less 
metallic character than either of the other kinds, unless it has been deposited with 
extreme slowness ; it is then sometimes bright and black like a blackleaded surface of 
iron ; its cohesion is then also greater, and its fractured surface black and bright. The 
specific gravity of one specimen which had been formed moderately slowly was 5'27 at 
60° Fahr. 
105. Repeatedly in depositing this variety in a coherent state at a moderate speed, I 
observed at the lower part of the deposit on each side of the cathode horizontal lines 
about f ths of an inch apart, of a lighter colour than the rest of the deposit. The con- 
trast of colour was caused by a black powdery deposit adhering to the other portions and 
not upon the lines, and appeared to be more prominent at the lines ; but what was the 
cause of the lines I have not ascertained. 
106. On immersing dry pieces in water a hissing sound is produced, evidently by 
powerful absorptive action, and numerous bubbles of gas are. evolved from the whole of 
its sui’face during about five or ten seconds, and a few small ones afterwards. 
107. A small piece, ^th of an inch thick, placed upon platinum foil upon mercuiy at 
200° Fahr. and touched by a red-hot wire, exhibited no signs of evolving heat; but with 
the mercury at 338° Fahr., and touched as before, it discharged its heat feebly and 
slowly, and evolved iodide of antimony. A second similar piece, heated from 300° Fahr. 
upwards upon platinum foil upon mercury, discharged its heat with evolution of iodide 
of antimony when the mercury had attained a temperature of 350° Fahr. ; but the 
thermic action was feeble, and occupied about 20 seconds. Its temperature of sudden 
discharge appears therefore to be about 340° Fahr., and the amount of heat evolved is 
apparently very much less than with the other varieties. If exposed to strong sunlight 
during two hours, it acquires a reddish-brown colour externally. 
108. The dried substance, fused in an analysis-tube (82.), gave 77*76 per cent, of a 
metallic button, and a solid, red, easily fusible sublimate, together with a httle moistm'e, 
manifestly teriodide of antimony, and a little aqueous hydriodic acid. 
109. The electro-chemical equivalent of this variety was examined in the same manner 
as the preceding one (102.). In two determinations, first with slow action (0*5 gr. 
per square inch per hour), 50*39 parts of deposit were obtained; and second, with veiy 
slow action (0*2 gr. per square inch per hour), 48*07 parts were obtained for every single 
equivalent, or 42*5 parts in the chloride solution. The numbers were lessened in con- 
