instituted with Lucifer Matches and others ignited by friction. 359 



ments, the latter method generally furnished the most trust- 

 worthy results. 



By far the greater number of matches experimented with did 

 not inflame at temperatures ranging up to, and somewhat ex- 

 ceeding, that of boiling water. Some few, which contained a 

 large proportion of ordinary phosphorus in their igniting com- 

 position, inflamed at temperatures ranging between 77° and 

 100° C. Three or four different kinds inflamed after some time 

 when surrounded by boiling water, though a considerably higher 

 temperature was required for their ignition by contact with heated 

 mercury or in an air-bath. This difference was traced to the 

 slight but continuous concussions to which the head of the match 

 was subject in consequence of the ebullition of the water. Some 

 other matches (the cylindrical kinds from Austria), the tips of 

 which were coated with varnish, only inflamed after a time when 

 surrounded by boiling water, and required a temperature of 

 102° C. for their ignition by immersion into mercury. Upon 

 partially removing the thin coating of varnish from the tips of 

 these matches, they were inflamed at once at 96° C. Many of 

 the matches tried did not inflame spontaneously below 115° C; 

 two or three varieties of common lucifers required a temperature 

 of 138° C. for their ignition ; and one description, containing a 

 comparatively small proportion of ordinary phosphorus, did not 

 inflame below 160° C. 



In exposing the matches separately or in numbers (i. e. a box 

 full) to gradually increasing temperatures in an air-bath, it was 

 observed that the sensitiveness to ignition by heat alone (and by 

 friction also) diminished in proportion to the period of exposure 

 of the match to elevated temperatures. Thus, it was repeatedly 

 found that a match was almost directly ignited on its introduc- 

 tion into a heated atmosphere in which matches of the same 

 kind had been for some time exposed without any such result, 

 they having been gradually raised, together with the air, to the 

 particular temperature. The extent to which the sensitiveness 

 of a match could be reduced by long exposure to heated air was 

 remarkable, though it is a result which must be expected to arise 

 from the promotion, by heat, of the gradual volatilization and 

 oxidation of the phosphorus in the igniting material. 



The order of sensitiveness to ignition by friction or percussion 

 of a match was found to correspond with its susceptibility to 

 ignition by heat alone, in the case of those which contained ordi- 

 nary phosphorus and chlorate of potassa, provided that glass was 

 included in the composition of the igniting material. Where 

 this was not the case, the matches, though they might be more 

 sensitive to the effects of heat alone than others, on account of 

 the predominance of phosphorus in them, were considerably less 



