Proceedings -OF the Polytechnic Association. 1005 



person holding it ; if it is petroleum, immediate ignition may 

 take place, and the heat of its burning is so intense that everything 

 combustible is soon involved in flames. On the other hand, if whale 

 or lard oil is thus scattered it is comparatively slow to ignite, and 

 slow to burn, giving ample time for those present to prevent the occur- 

 rence of damage. 



The superior light afforded by petrolenra is the great inducement 

 for its use, and when properly prepared and refined it is not unpleas- 

 antly odorous, and tlie only precaution requisite is to avoid breaking 

 lamps, spilling the oil, and thus setting fire to the premises. 



Mr. C. E. Emery said when a lamp is lighted in a warm room, the 

 temperature of the gas within the tube of the lamp is high. Now 

 when this lamp is taken into a cold room, the gas is condensed, so as 

 to take in some of the outer air, which mixes with the gas ; and again 

 when the lamp is brought back to the warm room, this explosive 

 mixture is forced out, and is apt to cause an explosion. 



After a lengthy but interesting discussion the Association adjourned 

 to meet again in one week. 



March 11, 1868. 



Professor S. D. Tillman in the chair ; Mr. C. E. Emeky, Secretary. 

 The attendance at the meeting was unusually large, and it was 

 quite evident that the room in which these meetings are held is 

 entirely too small for the purpose of the association. The chairman 

 opened the proceedings by reading a series of exceedingly valuable 

 and interesting notes on the scientific novelties which have .been 

 recently brought forward. 



KiTROUS OXYD FOK NeUEALGIA. 



The first item related to the recent discovery of Dr. G. Q. Colton, 

 of 'New York, who claims that nitrous oxyd, or laughing gas, is a 

 specific for neuralgia. The doctor has successfully administered the 

 laughing gas to 34,000 persons, for the purpose of performing dental 

 operations without pain, and, by persistent personal efforts in Europe, 

 has at last succeeded in introducing the use of this for similar 

 purposes in Paris and London. In many instances persons afflicted 

 with asthma have been greatly relieved. 



Dr. L. Feuchtwanger remarked that chloroform is unquestionably 

 a better anaesthetic than nitrous oxyd. Owing to the short duration 



