322 MISCELLANEOUS. 



because it is liable to the re-action of the nitric 

 acid ; and while any of the acid adheres to it, it is 

 very subject to the action of light. From 100 

 grains of mercury, about 120 or 130 of the powder 

 are obtained. 



This powder, struck on an anvil with a hammer, 

 explodes with a stunning disagreeable report ; and 

 with such force as to indent both the hammer and 

 the anvil. Three or four grains are as much as 

 ought to be used for such experiments. 



To make the Arbor Diana?, or Tree of Diana. 



Take half an ounce of fine silver, and two 

 drachms of mercury, and dissolve them separately 

 in a quantity of aqua fortis. When the solutions 

 are perfectly made, mix them together, and pour 

 them into a pint of common water, and stir it 

 about, that the whole may be well mixed. Keep 

 this preparation in a bottle well corked. In a glass 

 globe, or other vessel, put the quantity of a small 

 nut of the amalgam of silver with mercury, and 

 pour three or four ounces of the above liquor 

 over it. After some hours there will arise from 

 the little globular amalgam small branches, which, 

 by increasing, will form a beautiful kind of shrub 

 or tree of silver. 



To make a Tree of Silver on Glass. 



Put a few drops of the solution of silver in aqua 

 fortis on a piece of glass, and having formed a bit 

 of copper or brass-wire to represent a tree with its 



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