THE INFLUENCE OF IODINE. 
605 
The following history of the iodine, perhaps, may not be con¬ 
sidered uninteresting to the veterinarian. It is a simple body, 
discovered in 1813 by M. Courtois, in the mother waters formed 
in the preparation of soda, where it exists in the form of hydrio- 
date of potash. These waters are obtained by burning the dif¬ 
ferent fuci which grow on the sea-shores of Normandy, lixiviating 
the ashes, and concentrating the liquor. 
- The name of iodine is derived from the Greek word on 
account of the blue colour of its vapour. It is solid at the ordi¬ 
nary temperature in the form of small greyish crystals. It 
fuses at 338° Fah. and volatilizes at 347° Fah., forming a very 
beautiful violet-coloured vapour. 
Iodine is soluble in ether, and in spirit of wine: it has the 
property of forming an acid with hydrogen, and another with 
oxygen. 
Hydriodic acid is obtained by pouring water on an ioduret of 
phosphorus made of eight parts of iodine and one of phospho¬ 
rus, and distilling the liquor. 
Hydriodic acid can be united to a great number of bases, and 
forms neutral salts with some of them, of which the hydriodate 
of potash has hitherto been the most extensively employed in 
medicine. - ' 
The hydriodate of potash may be made by pouring on iodine, 
in its metallic state, a solution of potash: an iodate and a hy¬ 
driodate are then formed, which may be separated by means of 
alcohol, which only dissolves the latter of these salts. The 
hydriodate may then be obtained by evaporation. 
M. Coindet, a physician of Geneva, first used iodine in me¬ 
dicine. He employed it in the treatment of goitre with very 
marked effects. These trials were repeated by several medical 
practitioners in France, Switzerland, and Great Britain ; and 
their observations have proved that we now possess in iodine 
an efficacious remedy for the removal of a disease which has been 
hitherto cured with difficulty. 
Mr. Youatt has used it in bronchocele in the dog and swine 
with advantage; and in cattle, he says, it scarcely ever fails to 
disperse enlargements of the glands, or hardened tumours, whe¬ 
ther under or at the side of the jaw, or round the joints. In 
indurations of the udder he has likewise found it singularly 
successful. 
We know of no important part that iodine performs in nature’s 
works. It seems of no value to art, and is not necessary to life. 
It is made by the chemist, though it is beyond his art to unmake 
it. We have called it a simple substance; we consider it as 
such, from the fact of its having hitherto resisted all the efforts 
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