1§2 Scientific Intelligence. 



fusible metal, formed of 118 grains of filings of tin, 207 grains of filings of 

 lead, and 286 grains of pulverised bismuth, be incorporated in a dish of 

 calendered paper, with 1616 grains of mercury, the temperature will in- 

 stantly sink from 65° to 14.° M. Dobereiner thinks, that it might fall so low 

 as the freezing point of mercury, if the experiments were made at a tem- 

 perature a little under 32.° — See Schweigger's Neue Journal, xii. p. 182. 



21. Refrigerating Salt. — If we mix 57 parts of muriate of potash, with 

 32 of muriate of ammonia, and 10 of nitrate of potash, a refrigerating salt 

 will be produced. This salt, put into four parts of water, and quickly 

 agitated, will make the thermometer descend from 20° to 5° below zero, 

 in Reaumur's thermometer. — Vauquelin, Journal de Pharmacie. 



22. On thePectic or Coagulating Acid. — This new acid has been discovered 

 by M. H. Braconnot, and receives its name from ctskt/;, coaguhm, in con- 

 sequence of its resembling a jelly or gum. It is found in all vegetables. It is 

 sensibly acid. It reddens turnsole paper. It is scarcely soluble in cold water, 

 but more so in hot water. It is coagulated into a transparent and colourless 

 jelly by alcohol, by all the metallic solutions, by lime-water, water of 

 barytes, the acids, muriate and sulphate of soda, and nitre, &c. It 

 forms, with potash, a very soluble salt, consisting of 85 parts of lead, and 

 15 of potash. This salt has the remarkable effect of communicating to 

 large masses of sugar and water the property of gelatinising, which ren- 

 ders it of great use to the confectioner. M. Braconnot, in this way, prepar- 

 ed aromatised jellies, perfectly transparent and colourless, and very agreeable 

 to the taste and the eye. He alsomade, with rose-water, coloured with a little 

 cochineal, rose-jelly of exquisite taste. — Ann. de Chim. torn, xxviii. p. 173. 



23. Iodine in Mineral Waters. — Iodine was first discovered in mineral 

 waters by M. Angelini, who found it in the salt water of Voghera, and in 

 the water of Sales in the Voguerais. M. Cantu, Professor of Chemistry 

 at Turin, surprised at the wonderful effects of the sulphurous water of 

 Castel Nova d'Asti, in the treatment of goitres, and other glandular mala- 

 dies, examined it chemically, and found it more rich in iodine than any 

 other. — Mem. de Torino, torn, xxix.p. 221. 



III. NATURAL HISTORY. 



MINERALOGY. 



24. Apatite in Salisbury Crags, Edinburgh. — Apatite has been lately 

 found in Salisbury Crags. It occurs in the greenstone near the southern ex- 

 tremity, in a mixture consisting chiefly of white calcareous spar, red albite, 

 and a blackish-green soft substance, nearly allied to serpentine. Particularly 

 in the latter, the plain asparagus-green crystals of apatite are very distinct, 

 and possess a high degree of lustre. Their form is that of a regular six- 

 sided prism, terminated by a plane perpendicular to the axis, and having 

 frequently also the lateral edges replaced by another six-sided prism. The 

 length of these prisms is rarely so much as two lines, but their thickness 



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