324 



Mr. Buddle on Mining Records. 



of ventilation generally pursued in those collieries was by shething and 

 coursing the air, two and two, that is to say, the current of air was carried 

 up two boards and down two, making 4 boards in each sheth ; and the par- 

 tial working of the pillars was effected by working 5 yards off the end of 

 each pillar of coal in the open or loose wall, the width of which was thereby 

 extended to 12 yards. 



By this plan the produce of the seam was increased from If to if parts 

 or from 39^ to 54^ per cent. This, by experience, was found to be the 

 maximum produce that could be obtained from the seam, without inducing 

 a creep, before the working of the prescribed portion of the pillars could 

 be worked out of the districts already described. The Diagram annexed 

 will explain this matter more clearly. 



This mode of working the pillars was pursued till the year 1809, when I 

 introduced the system of " pannel work," which consisted in preparing the 

 then remaining field of whole coal for the subsequent working of the pil- 

 lars, by dividing it into districts or pannels, varying in area according to 

 circumstances ; the districts or pannels being formed by leaving barriers of 

 coal round them. My object in this plan of working was to combine ven- 

 tilation with the working of the pillars. This mode of working was pursued ■ 



