1835.] the Advancement of Science. 197 



at present, were the introduction of very strong glass, to 

 cover the gauze externally. The glass is again guarded 

 by strong ribs of iron, so that the lamp may be exposed to 

 considerable shocks without danger of injury. A contri- 

 vance was also described by which the air was allowed to 

 enter from below, by means of a gauze tube, but so managed, 

 that the gauze could not be reached by the workmen. 



Various improvements upon the Davy lamp were noticed 

 by different members. 



Mr. Graham stated, that he had been paying consider- 

 able attention to the subject, and had found that when the 

 gauze was steeped in an alkaline solution, the flame was pre- 

 vented from passing so readily, and corrosion was obviated.* 

 He considered the only adequate provision against accident 

 to be the employment of a double gauze cover. 



3. Mr. Kane read a communication in reference to pyr- 

 oxylic spirit. The experiments which he had made upon this 

 substance, corroborate the opinion of its composition enter- 

 tained by Dumas and Pelligot, who term it methylene, viz. 

 that it is a compound of an atom of carbydrogen, and 1 atom 

 water, having for its atomic weight 2. He had examined 

 the action of sulphuric acid upon the liquid, and had ob- 

 tained by distillation, an acid capable of forming salts with 

 bases. The composition of several of these, he had ascer- 

 tained by determining the proportions of the acid, (or sulpho- 

 methylic acid) and base, and considering the loss to be me- 

 thylene. The compound with lime, consisted of 1 atom lime 

 4- 2 atoms sulphuric acid + 1 methylene. 



Some discussion took place in reference to the double 

 atoms, of which the organic bases are stated to consist, 

 according to the views of Continental chemists. Consider- 

 able misunderstanding was exhibited in many of the obser- 

 vations offered upon this point. But it is unnecessary to 

 repeat the statement of the various theories, as this has 

 been already done in the previous number of this journal, 



4. Mr. Fox described an experiment which he had made, 

 with regard to the effect of melted iron upon the magnet. 

 He found that no action was exerted upon it. Hence, this 

 is an argument against the idea of a central fire. 



* Tliis is agreeable to the results obtained by Dr. Thomas Thomson many 

 years ago. 



