CHEMISTRY. 209 



neous fibre resists most tenaciously, when undergoing oxidation, 

 and since its oxygen is insufficient to convert all the carbon into 

 carbonic acid, various compounds of hydrogen result, undoubt- 

 edly aided by a coetaneous decomposition of water. From starch 

 another acid is produced besides carbonic, noticeable for great 

 solubility of its lime salt. 



The decomposition of nitrate of silver in solution by organic 

 substances seems to be due to a disengagement of hydrogen gas, 

 which reduces the nitric acid to a lower oxide of nitrogen ; a pro- 

 cess probably analogous to that which affects nitre in the soil or 

 manures. This reducing action in watery infusions ceases after a 

 time, apparently in consequence of the appearance of some algre. 

 Those sulphurets which at ordinary temperature exhale the pecu- 

 liar odor, appear to do so because they decompose water on the 

 surface ; in their solution the presence of hydrogen is readily in- 

 dicated by the galvanic test. Though usually negative com- 

 pounds, the solutions (of pentasulphide of potassium) show posi- 

 tive electricity. Henrtci, Poggendorf's Annalen. 



SUMMARY OF CHEMICAL NOVELTIES. 



Treasure in the Blast' Furnace. On page 168 of Dr. Percy's 

 work on Iron and Steel, he notices the discovery of Sonnenschein 

 at one of the furnaces of the Marienhute, in Upper Silesia. He 

 tapped the hearth below the tap-hole, and obtained a considerable 

 quantity of lead and silver, which had settled to the bottom in 

 virtue of its superior specific gravity. Not that lead and silver 

 are contained in all iron ores ; but in the ores of Weardale there 

 are indications of lead, silver, and zinc, as well as manganese, 

 and so Mr. William Thomas, manager of the Tow Law Furnaces, 

 somo time ago determined to see what he could find b} 7 tapping his 

 hearth at the very bottom. He drew off a charge of lead contain- 

 ing a considerable percentage of silver, and he sold it for more 

 than we dare repeat, but it was a good deal. The discovery of 

 large quantities of silver in their blast furnace hearths caused no 

 little excitement. Mr. Thomas is now tapping his lead and silver 

 daily from below the iron, and he is selling his furnace fume, 

 which contains half its weight of metallic zinc. Engineering. 



Olyconine A New Glycerole. To contain this compound, M. 

 Edmoncl Sichel employs 4 parts (by weight) of yolk of egg, and 

 5 parts of gtycerine, which he mixes simply in a mortar. It has 

 the consistence of liquid honey, and is unctuous like the fatty sub- 

 stances, over which it has the advantage of being easily removed 

 by water. It is unalterable, a specimen having been left exposed 

 to the air for 3 years with impunity. Applied to the skin, it 

 forms on the surface a varnish, which protects it from the contact 

 of the air. These properties render it serviceable for broken sur- 

 faces of all kinds, particularly for burns, eiysipelas, and cutaneous 

 affections. American Journal of Pharmacy. 



Green Vitriol from Iron Slag. A sulphate of iron, which is 

 esteemed by dyers, according to M. Ch. Mene, ma} 7 be produced 

 from the slag of iron forges more cheaply than in any other way. 



