396 Miscellaneous Intelligence. 



carried up by the gas. Strong sulphuric acid leaves graphite, 

 and easily combustible carbon. Tsitric acid of specific gravity 

 1.3, whether urged by heat or not, seems to act irregularly; 

 leaves of graphite being evolved, which as they fall off, or are 

 separated from, the iron, allow the action to be renewed, they 

 seem to form an actual mechanical impediment to the solution; 

 a part of the carbon is dissolved by the acid, and the residuum 

 is mostly graphite mixed with carbon in the state of brown 

 powder. 



The graphite thus obtained is insoluble in acids, and alkalis, and 

 quite pure. Heated to redness in the atmosphere, it disappears 

 slowly, leaving no residuum: 18 grains of it placed in a muffle 

 heated to whiteness, required 4 hours for its combustion ; it gra- 

 dually decreased in bulk, produced no flame, and left a minute 

 film of white silica. When the process was interrupted, the only 

 difference seen between the calcined and uncalcined graphite was, 

 that the leaves of the former, if held against the light, appeared 

 transparent in some places, and exhibited a peculiar fibrous struc- 

 ture, which the uncalcined portion did not possess : melted with 

 nitre, it was slowly consumed, and the salt remaining, left no re- 

 siduum in water : heated with sulphate of potash, it did not con- 

 vert it into sulphite. 



Thus, then, the graphite in gray raw iron is not what it has 

 been supposed to be, a combination of carbon and iron, but pure 

 carbon, or its metallic base. Whether natural graphite be also 

 a pure carbon metal, or really a combination of carbon and iron, 

 is yet to be determined. — Phil. Mag. lxvi. 290. 



10. Preservative against Rust. Stockholm, 9th Sept., 1S25. — M. the 

 Councillor of State of Loevenhielm, Swedish Ambassador in 

 France, during his residence in Paris, received certain proposi- 

 tions from the house of Mazet and Co., tending to give to the pro- 

 prietors of the mines in Sweden, for the sum of 300,000 francs, 

 a secret ; the use of which is, by means of a metallic composition, 

 to preserve all iron goods from rust. The colleges of mines and 

 of commerce, with the Academy of Sciences, and the delegates of 

 the iron-office, were directed to examine these propositions, and 

 they thought fit to adopt them. — Rev. Ency. xxvii. 899. 



11. Combinations of Antimony with Chlorine and Sulphur. — 

 The following estimations of the composition of these bodies is by 

 M. Rose. The crystallized compound of antimony and chlorine, 

 obtained by distilling the pulverized metal with corrosive subli- 

 mate, was supposed, from theoretical views, to be a compound of 

 three proportionals of chlorine and one of the metal. It was ana- 

 lyzed by bringing it into solution in water by tartaric acid, preci- 



