534 MATEllIA ^lEDlCA 



nitre and sublimed sulphur, and throwing the mixture, in small 

 portions at a time, into a red-hot crucible. As soon as the de- 

 flagration is finished, the salt is to be allowed to cool, and then 

 put it into a close-stopped glass vessel. Its properties are similar 

 to those of sulphate of potass, and it is sometimes combined with 

 aloes as a laxative or cathartic. It passes through the kidneys 

 undecomposed. 



SAL VOIiATILE. This term is indiscriminately applied 

 to compound spirit of ammonia, and prepared ammonia, or 

 smelling suits ; but the former is often distinguished by the name 

 of spirit of sal volatile. 



SALIX CAPKEA. The Willow. There are three varieties 

 of Avillow, the barks of which are tonic and astringent, and have 

 been successfully substituted for Peruvian bark. A preparation 

 called salacine is now made from Avillow bark, which possesses its 

 tonic princii)le in a concentrated state, in the same manner as 

 quinine does that of cinchona. The dose may be from ten to 

 thirty grains, or perhaps more in some cases, twice or thrice a 

 day. 



SALT, COMMON. — 5'ofZcE Murias. See Muriate of 

 Soda. 



SALTPETRE.— Po^«55« Nitras. See Nitre. 



SALT OF STEEL, SULPHATE OF IRON, or VL 

 TRIOLATED IROl:^. — Sulphas Ferri. A combination of 

 sulphuric acid and iron. This is by no means so remarkable 

 for its tonic power in the horse, as in the human subject ; but it 

 is said to possess this quality, and is often given in doses of from 

 one or two to four drachms. See Iron. 



SALT OF TARTAR, or WORMWOOD. Pure carbo- 

 nate of Potash. — PotusstB Carhonas Purissimus. Sec Potasu 

 and Alkalies. 



SALTS. When an acid combines with an alkali, earth, 

 or metallic oxide, it is termed a salt. The alkali, earth, or me- 

 tallic oxide is denominated the base, and when neither the acid 

 nor the base predominates, it is called a neutral salt. When, 

 on exposvu'e to atmospheric air, it is either reduced to powder or 

 becomes covered with a white crust, it has received the appella- 

 tion of an efflorescent salt ; but if it absorb moisture from the 

 atmosphere, it is termed a deliquescent salt. 



The name of each salt is compounded of two words ; the one 

 indicating its acid, the other its base. Thus Glauber's salt, 

 which is composed of sulphuric acid and soda, is called sulphate 

 of soda. Nitre, which is compounded of nitric acid and potass, 

 is termed nitrate of potass. 



When a salt is formed with an acid not completely oxygen- 

 ised, it terminates in ite instead of ate, as phosphite of soda ; 

 but if the salt contain acid in excess, the word siqyer is prefixed 



