24 HISTORICAL INTRODUCTION TO CHEMISTRY CHAP. 



(c] Adds dissolve metals, e.g., Oil of Vitriol and Muriatic acid 

 dissolve Iron ; Oil of Vitriol (concentrated) and Aqua Fortis 

 dissolve also Copper, Mercury and Silver ; Aqua Regia 

 dissolves Gold. 



The action of acids and alkalis on vegetable tinctures such 

 as the blue-fluorescent extract of " Lignum nephriticum," syrup 

 of violets and cornflowers, and the purple juice of ripe privet- 

 berries was described by Boyle (Experiments on Colours, 1663). 



D. SALTS. 



Many salts can be prepared artificially by the action of Acids 

 on Metals, Alkalis (Soda and Potash) and earths. Amongst 

 the salts which were prepared and examined at an early date 

 the following may be noted : 



(a] Vitriols or Sulphates. From Metals : Green Vitriol, 

 Sulphate of Iron, or Ferrous Sulphate, FeSO 4 , 7H 2 O ; Blue 

 Vitriol, Sulphate of Copper, or Copper Sulphate, CuSO 4 ,5H 2 O. 



From Alkalis : Glauber's Salt, Sulphate of Soda, or Sodium 

 Sulphate, Na 2 SO 4 , ioH 2 O ; Vitriolated Tartar, Sulphate of 

 Potash, or Potassium Sulphate, K 2 SO 4 . 



From Earths : Gypsum or Selenite, Sulphate of Lime, or 

 Calcium Sulphate, CaSO 4 , 2H 2 O ; Epsom Salts, Sulphate of 

 Magnesia, or Magnesium Sulphate, MgSO 4 , 7H 2 O ; Alum, 

 Sulphate of Potash and Alumina, or Potassium Aluminium 

 Sulphate, KA1(SO 4 ) 2 ,I2H 2 O. 



(b] Nitres or Nitrates. Nitre or Saltpetre, Nitrate of Potash, 

 or Potassium Nitrate KNO 3 ; 



Chile Saltpetre, Nitrate of Soda, or Sodium Nitrate, NaNO 3 ; 

 Lunar Caustic, Nitrate of Silver, or Silver Nitrate, AgNO 3 . 

 Also Nitrates of Lead, Copper, Iron and Mercury. 



(c] Muriates or Chlorides. Muriates or Chlorides of Iron 

 (FeCl 3 ), Copper (CuCl 2 ), and Gold (AuCl 3 ). Common Salt 

 Muriate of Soda, or Sodium Chloride, NaCl ; 



Sylvine, Muriate of Potash, or Potassium Chloride, KC1 ; 

 Muriate of Magnesia or Magnesium Chloride, MgCl 2 ; 

 Muriate of Lime or Calcium Chloride, CaCl 2 . 



(a] Acetates. Sugar of Lead, Acetate of Lead, or Lead Ace- 

 tate, Pb(C 2 H 3 2 ) 2 ; 

 Acetate of Copper or Copper Acetate, Cu(C 2 H 3 O 2 ) 2 , pre- 



