404? Intelligence and Miscellaneous Articles. 



washed in water, then mixed with this liquid, the mixture was heated 

 in a kind of Papin's digester until the interior pressure amounted 

 to eleven atmospheres; siliceous grains were precipitated produced 

 from the milk of lime. The matter was then taken and redissolved 

 anew in hydrochloric acid; the solution having been filtered, it 

 was again filtered through chalk of Meudon, which had been passed 

 through very fine cambric, by means of water, to separate the grains 

 of quartz from it. Oxide of iron was deposited in the chalk. 

 When the filtration was difficult, the liquor was acidulated. At the 

 end of fifteen days the Meudon whitening was again strained through 

 the cambric, and the part which had not passed was treated with 

 hydrochloric acid ; small opalascent siliceous concretions were ob- 

 tained, of which several have the form of crowns and are split from 

 the centre to the circumference ; they are not fusible with the blow- 

 pipe and scratch glass; those which were coloured being moderately 

 heated, acquired a smoky tint in consequence of the organic matter 

 which they contain. 



" Fourth Experiment. — 125 grammes of powdered Meudon whiten- 

 ing were put into a glass tube about two inches in diameter, and 

 four feet and a half in height; the lower part of the tube was then 

 closed with a piece of linen rag intended to serve as a filter. Af- 

 terwards water was put into the tube, and the whitening was shaken 

 so as to mix it well. After having completely filled up the tube 

 with this water, some water very weakly acidulated with hydro- 

 chloric acid was prepared ; and in proportion as the water first put 

 into the tube filtered away through the whitening and the linen 

 upon which it rested, acidulated water was poured into the tube. 

 The filtered water deposited by degrees in a bottle in which it was 

 received, crystalline grains of carbonate of lime ; and at the same 

 time the linen serving as a filter, became covered over a great part 

 of its exterior surface with a crust which, examined with a mag- 

 nifying glass, had the appearance of saccharoidal marble. The 

 experiment lasted about three months. The quantity of whitening 

 of Meudon which was dissolved during the time that the filtration 

 continued was about 75 grammes, that is to say, a little more than 

 the half of all the whitening which had at first been put into the 

 tube." — Comptes Rendus, No. 25. June 1837. 



NEW CARBURETS OF HYDROGEN, RETINNAPTHE, RETINGLE, 

 RETINOLE, AND METANAPHTALENE. 



MM. Pelletier and Walter have examined the products obtained 

 during the conversion of resin into gas for gas lights; the results are 

 stated to be : 



1st. The instant the resin falls into the red-hot cylinder there are 

 formed with the gas a certain number of extremely hydrogenated 

 compounds which have been separated by chemical analysis. 



2nd. Among these substances there occur three new carburets 

 of hydrogen, to which the author has given the names of retinnapthe, 

 r&ingle, and retinole; these are all liquid : there are two solid carburets 

 of hydrogen, naphtalene, already known, and mitanaphtalene, a new 

 compound. 



