56 F. B. GUTHRIE AND A. A. ATKINSON. 



to be thus affected, was in air of the following composition, fire- 

 damp being absent : — 



Oxygen 15 30 



Carbon dioxide 3 38 



Nitrogen 81-32 



100-00 



Referring again to the table of analyses from the Hamstead 

 mine, the further point is to be noticed that the temperature in 

 the Lambton Heading, Wallsend Colliery, was considerably lower; 

 it was in fact from 1 to 3 degrees Fahrenheit lower than the shade 

 temperature at the surface taken 1 J hours later. 



Taking all the above facts into consideration, it appears, that 

 although the air in the Lambton heading was not absolutely pure, 

 it was not sufficiently vitiated as to be injurious to the health of 

 those travelling in it. 



The inconvenience complained of was probably due to the 

 following causes : — 



1. The distance to be travelled was considerable (1^ to 2 miles). 



2. The walk was at the end of a day's work. 



3. The men walk as rapidly as possible. 



4. In going outbye, they are obliged to walk with the air 



current instead of against it. 



Samples from Burwood Colliery. 

 These were taken in consequence of complaints received that 

 niners suffered from headache whilst undercutting or "holing" 

 <;he coal. 



Sample No. 1 was taken from the face of main east cross-cut 

 in the return airway near the Dyke. Time 12 noon. Temper- 

 ature 76*5 degrees F. Air current about 16,000 cubic feet, per 

 minute, for 48 men, 5 boys, and 5 horses; being 272 cubic feet 

 per individual. 



Sample No. 2 taken in No. 30 A bord, being the last in split 

 and near return. Sample taken from freshly cut holing. Time 

 12-25 p.m. Temperature 79 degrees F. 



