CUPRUM. 65 



after the manner of fat. It has no appreciable effect on the 

 blood. 



3. SPECIFIC ACTION AND USES. 



Silver becomes locked up in all the connective tissues of the 

 body, in the metallic f orm, staining exposed parts a dusky black 

 brown, incapable of removal. It probably, therefore, remains 

 inert within the body; but some authorities believe that it 

 affects the nervous tissues, and recommend it in epilepsy, 

 chorea, and locomotor ataxy. The permanent unsightly dis- 

 coloration of the skin, which comes on after its use for several 

 months, is a serious objection to its employment. 



4. REMOTE LOCAL ACTION. 



As we have just seen, silver once admitted to the tissues is 

 not excreted. A certain amount has, however, been found in 

 the urine ; and a proportion always passes through the bowels 

 unabsorbed, appearing on the faeces as sulphide. No use is 

 made of these facts. 



5. ACTION AND USES OF THE DIFFERENT SALTS OF SILVER. 



The Nitrate is almost invariably used both externally and 

 internally. The Oxide is less irritant, and is chiefly given in- 

 ternally in the form of pill. 



CUPRUM. 63-5. COPPER. 



The sulphate is the only salt of copper employed 

 medicinally, although other compounds, as well as the 

 metal itself, are introduced into the Pharmacopoeia as 

 tests. 



1. Cupri Sulphas. Sulphate of Copper. C 

 5H 2 <T~ 



Source. Made by heating Sulphuric Acid with Copper, dis- 

 solving the soluble product, evaporating and crystallising. 



Characters. A blue crystalline salt in oblique prisms. 

 Solubility, 1 in 3 of water. 



Impurity. Iron. 



Lose. As an astringent or tonic, J to 2 gr. ; as an emetic, 

 6 to 10 gr. 



From Cupri SidpJias is prcpand : 



Jrkilphate of Copper. Anhydrous. CuSO 4 . A yel- 

 lowish-white powder made by heating sulphate of copper 

 to 400 Fahr. Used in testing. 

 F 8 



