168 Miscellaneous Intelligence. 



10. On the presence of Iodine in the Waters of Sales, Piedmont.— 

 The waters of Sales spring in considerable quantities from an argilo- 

 calcareous ground at the foot of a hillock, on the left-hand side of 

 the torrent Stafford, near the road to Godiaso, not far from Sales, in 

 the province of Voghera. They are turbid and of a faint yellow 

 colour. They have a strong odour approaching to that of urine, or 

 a muriatic residuum ; their taste is brackish and sharp.; hubbies of 

 air constantly rise from the bottom of the reservoir containing them. 

 Their temperature is that of the atmosphere ; their specific gravity 

 1.0.502. In 1788 the Canon Volta analyzed them, and found a 

 twelfth of muriate of soda. In 1820, M. Romano repeated the ana- 

 lysis, and found muriate of soda, several earthy muriates, and a little 

 oxide of iron. M. Laur. Angelina, of Voghera, on using starch as a re- 

 agent, found a blue colour produced in the water, indicating the pre- 

 sence of iodine, and. using the process generally adopted with the 

 mother waters in the manufacture of soda, he succeeded in procuring 

 a certain quantity of iodine from the water. 



It is remarkable that, for a long time, the water of Sales has been 

 administered successfully in scrofulous cases, and in cases of the 

 goitre. — Jour, des Mines, viii. 203. 



20. Evolution of Gas during Metallic precipitation. — M. Rivero 

 has remarked, that inflammable gas is developed when zinc is made 

 to act on chloride of silver to reduce it. M. Despretz has since 

 remarked, that in the precipitation of one metal by another, gas is 

 always liberated when the two metals form an energetic voltaic com- 

 bination ; thus it will happen with any two of the three metals, 

 silver, copper, and zinc. Its source, therefore, is voltaic electricity. 



21. Electro-Magnetic effects of Alkalies, Acids, and Salts, by M. 

 Yelin. — The magnetic needle used by M. Yelin, was nearly 1.5 

 inches long, and .008 of an inch in diameter. It weighed little more 

 than half a grain, and was delicately suspended by a spider's web, 

 from a rod passing through the top of a glass cylinder, so that it 

 could be raised or lowered at pleasure. The bottom of the instru- 

 ment is a piece of card-board, on which circles are marked and 

 divided, indicating the number of degrees through which the needle 

 may have moved. 



The conductor, whose state was to be indicated by this needle, was 

 sometimes a band of tin 0.4 of an inch broad, and 24 inches long; 

 sometimes a brass wire helix, which being brought up close beneath 

 the needle, formed a kind of condenser, and rendered the action 

 more sensible. 



1. The tin band was placed under the needle, both being parallel 

 to the magnetic meridian, a small glass was filled with muriatic acid ; 

 the end of the band, towards the austral pole of the needle, was 

 plunged into the acid, and in a few moments after, the other extre- 

 mity was immersed, immediately the austral pole went to the east. 

 The experiment being repeated, except that the end of the band, 



