gi2 Mr. Chenevix's Enquiries concerning the Nature 
Green sulphate of iron, poured into this mixed solution, caused 
a precipitate weighing 874. It was in the form of a fine blue 
powder, not resembling an amalgam, though wholly metallic. 
Its specific gravity I could not ascertain ; but all the mercury 
was expelled by heat. 
The reagents which I used in the following experiments, were 
recent muriate of tin, and green sulphate of iron. To bring the 
examples of anomalous precipitations, in mixed solutions of the 
metals, more clearly into view, it wifi be necessary to state 
the action of these salts, upon a solution of each metal when 
separate. 
By recent muriate of tin we have, with a solution of gold, the 
well known purple of Cassius. With platina, the colour of the 
liquor is much heightened. With mercury, there is a total re- 
duction. With copper, a reduction from the black oxide at 20 
per cent, of oxygen, to the yellow oxide at 11 ,5 per cent, of 
oxygen. With arsenic acid, a reduction to the state of white 
oxide. With silver, with lead, with antimony, no reduction. 
Green sulphate of iron reduces none of the metallic solutions, 
except those of gold and of silver. 
When mixed solutions of the metals are exposed to the action 
of recent muriate of tin, or of green sulphate of iron, we have 
the following results. 
Experiments 4, 5, 6, 7, and 8. Muriate of tin, poured into a 
mixed solution of gold and mercury, precipitates both metals 
together; and there are no traces of the purple. Mixed solutions 
of gold and antimony, also of gold and arsenic acid, are acted 
upon in the same manner. Mixed solutions of gold and copper, 
also of gold and lead, afford results similar to those of each 
metal when separate. 
