444 



Mr. W. Galloway. 



[Mar. 23, 



Date. 



ment. 



CD 

 cS 



& 



Length of the gallery 

 strewed with coal-dust. 





Position and weight 

 of heaps of 

 gunpowder. 



Distance travelled by 

 the flame. 









a 



























July, 



of expe 



si 



paper : 

 m. 



Sections with 



Sections with 



n each 



g 



o . 



£ s 



burnt 



In the closed 

 part of the 

 gallery. 



CD 3 



he end 

 .llery. 



tance. 



1881. 



| Number 



Total qui 

 damp em 



Sheets of 

 diaphiag 



doors shut. 



doors open 





Weight i 

 heap. 



Distance 

 diaphrag 



Whether 

 or not. 



In the op 

 part of tl 

 gallery. 



Beyond t 

 of the ga 



Total dis 







Cb. ft. 



No. 



No. 



Ft. 



No. 



Ft. 





Oz. 



Ft. 





Ft. 



Ft. 



Ft. 



Ft. 



19 



41 



42 



1 -876 

 1-876 



6 

 8 



6 

 6 



108 

 108 



1 

 1 



18 

 18 











? 

 ? 







?* 

 ? 



u 

 »» 



43 

 44 



1 -876 

 1-876 



6 

 6 



6 

 6 



108 

 108 



1 

 1 



18 

 18 











108 

 ? 



18 



15 



141 

 ?t 



M 



45 

 46 



1-876 

 1-876 



6 

 6 



6 

 6 



108 

 108 



1 

 1 



18 



18 











108 

 ? 



18 





126 



20 



47 



48 



1-876 

 1-876 



6 

 6 



6 

 6 



108 

 108 



1 

 1 



18 

 18 











? 







? 

 ? 



»> 



49 

 50 



1-876 

 1876 



6 

 6 



4 

 5 



72 

 90 



3 

 2 



54 

 36 











72 

 90 



50 

 36 





122 

 126 





51 



1-876 



6 



6 



108 



1 



36 











108 



18 



21 



147 





52 



1-876 



6 



7 



126 















108 







108 



ii 



53 



1-876 



6 



7 



126 















? 







? 





54 



1 -876 



6 



5 



90 



2 



36- 





"i 



2 



21 



22 



18{ 



burnt 



not 

 burnt 



J 90 

 1 



36 



4 



130| 



21 



55 



1-876 



6 



7 



126 





... 





3 

 2 



36 

 72! 



ial 

 18 1 



burnt 



not 

 burnt 



not 

 burnt 



H26 



!• 





27 



153 



>> 



56 



1 -876 



? 



7 



126 





... 





2 



36 ( 



not 

 burnt 









? § 





















2 



»{ 



not 

 burnt 



i 



) 











57 



1-876 



? 



7 



126 







4 



21 



burnt 



126 





22 



148 





58 



1-876 



? 



7 



126 







4 

 4 



21 



42 



burnt 

 burnt 



j 126 





8 



134 





















4 



21 



burnt 









" 



59 



1 -876 



6 



7 



126 





-j 





4 

 4 

 4 



42 

 65 

 21 



burnt 

 burnt 

 burnt 



j 126 





34 



160 





60 



1-876 



6 



7 



126 









4 

 4 

 4 

 4 



42 

 65 

 87 

 21 



burnt 

 burnt 

 burnt 

 burnt 



!• 







? || 





61 



1 -876 



6 



7 



126 









4 

 4 

 4 



42 

 65 

 87 



burnt 

 burnt 

 burnt 



}• 







? 





62 



1 -876 



6 



4 



72 



3 



54 











? 







100** 



ii 



63 



1 -876 



6 



3 



54 



4 



72 











54 



46 





* It was raining when the forty-first and forty-second experiments were made, 

 t R;dn had ceased when the forty-fourth experiment was made. 



j This result was obtained without putting in any fresh dust after the previous experiment was 

 made. 



§ The gallery bad not been swept out, and no fresh dust was added after the last experiment. The 

 soot was taken off the first and third heaps of powder, ihat had been left unburnt, and another heap 

 was substituted for the one that had been burnt in the middle. 



|| In this case and the next the explosion of the powder seemed to arrest the progress of the flame, 

 instead of accelerating it. 



There was fresh dust in the two first sections only. 



** This flame came out of the last two sections and swept the ground, coking the dust lying at the 

 three points it touched over an area of four or five square feet at each. 



It should again be mentioned that a thick cloud of coal-dust and 

 air was always created by the air- wave which emanated from the fire- 

 damp explosion and swept through both the closed and open parts of 

 the gallery, in advance of the flame. When this cloud emerged into 

 the open air, either by drifting sideways from the open sections, or by 



