Scientific Intelligence. — Mechanical Philosoi)hy. 179 



J 



duce the heat as not to affect the organs. Many pcr:.ons have per- 

 ished hi conflagrations, altogether from havhig ijioir organs of respi- 

 ration destroyed, as has been proved by tlie autopsy. It is possible 

 that those interior lesions may have been occasioned by lieatcd aqrjc- 

 ous vapor, which retains its caloric better than air. 



The grand duke of Tuscany has had six of these dresses prepared . 

 for the city of Florence. 



M. Aldini shewed before the Pliilosophical Society of Geneva, t!;at 

 a loose tissue of asbestus intercepts the flame of a caudle or spirit of 

 wine lamp, as well as a motanic gauze of the same contexture. This 

 gives new force to the objections to Davy's theory of die effect of 

 wire gauze, for in this case the metal, which is a substance of the 

 highest conducting power, is replaced by one which is a slow con- 

 ductor.— J5'/6. Ihiv.Aout, 1829. 



M. 



7. Pliwihago instead of oil in ivaickcs and chronomtiers.— 

 Hebert appears to have well ascertained that plumbago, well pre- 

 pared by rubbing and repeated washings, to remove all the particles 

 of gravel which are more or less found in the best specimens, is 

 preferable to oil in watch movements. It is apphed with a \m\v pen- 

 cil, either in powder or mixed with one or two drops of pure alcohol. 

 It adheres promptly to a pivot of steel, as^well as to the surface of 

 the hole in which it turns, so that the rubbing surfaces, no longer 

 present a metal to a metal, but plumbago to plumbago; they acquir- 

 ed a polish wliich yields only to that of the diamond; tlie retardation 

 from friction and the wearing becomes almost noUnng. An astro- 

 nomical clock made by M. Hebert, the pivots and holes of which, 

 and the teeth of the escapement had been covered on their sur- 

 faces with fine plumbago, fourteen years before, was taken apart 

 and examined by a committee of the London Society of Arts. The 

 surfaces of plumbago were found, for the most part, entire and per- 

 fectly polished, and a strong magnifying glass discovered not the 

 slightest w^ear, either in the pivots or the holes. (Trans. See. of 

 Arts, 46, p. AS.)— Idem. 



8, Optical Surgery.— M. Maunoih, professor of surgery at Ge- 

 neva, having performed the operation for cataract by extraction upon 

 a man eighty two years of age, weakened by an operation for hernia 

 which he had endured six weeks before, perceived to his regret, that 

 although the pupil remained of a beautiful black and perfectly intact, 



