54 



REPORT — 1861. 

 Table I. — vontitiwd. 



Date. 



Depth 



of the 



Pit. 



Tempe- Time in 



rature i hole, in 



of hole, minutes. 



I 



Quality of Measure, 

 or Strata. 



State of bore-hole, and other 

 remarks. 



1851. 

 June 9. 

 Aug. 14. 

 Nov. 7. 



„ 19. 



1852. 

 Feb. 6. 

 May 28. 



1857. 



yds. 

 358 

 373 

 403 

 419 



433 

 446 



4834 



487 



501 



51 1^ 



52H 



533 



539 



546 



555 



563 



569 



578 



589 



597 



608 



em 



621 



627 



6454 



651 



658 



669 



673 



683 



685 



717 



624 

 64 

 65 

 65f 



664 

 67 



67i 

 671 



684 

 68| 



69f 

 69| 

 71| 



'H 



''% 

 714 



72i 

 72i 

 72i 



72 



711 



72i 

 724 

 724 

 73^ 



74ir 

 75i 

 754 



m. 

 300 



61 

 360 

 120 



120 

 120 



75 

 75 

 60 

 120 

 135 

 130 

 150 

 150 

 130 

 120 

 120 

 180 

 90 

 120 

 150 

 180 



90 

 90 



140 



150 



120 



150 



185 



180 



180 



1200 



Warrant earth 



Tender blue shale 



Top shuttle mine roof. . 

 Rock bands 



Black shale 



Strong warrant earth.. . 



Dry hole, in dust, 5 men sinking. 

 Dry hole, in dust, 6 men sinking. 

 Dry hole, in dust, 6 men sinking. 

 Dry hole, in dust, 7 men sinking. 



Dry hole, in dust, 7 men sinking. 

 Dry hole, in dust, 6 men sinking. 



Dry 

 Dry 

 Dry 

 Dry 

 Dry 

 Dry 

 Dry 

 Dry 

 Dry 

 Red rock iDry 



Rock 



Shale 



Rock 



Blue shale 



Strong grit shale 



Warrant earth 



Blue shale 



Coal and earth.... 

 Grev rock 



Red rock , 



Red rock 



Red rock 



Grey red rock 



Rusty mine roof ., 

 Rusty mine floor.. 



Strong grit shale.. 

 Dark blue shale ., 



Gritty shale 



Gritty shale 



Dark blue shale .. 

 Bituminous shale 



Grey rock 



Dark blue shale... 

 Dark blue shale... 



Wet 

 Wet 

 Wet 

 Dry 

 Wet 

 Wet 



D17 

 Dry 

 Dry 

 Dry 

 Dry 

 Dry 

 Dry 

 Dry 

 Dry 



Black mine roof . 



hole, in 

 hole, in 

 hole, in 

 hole, in 

 hole, in 

 hole, in 

 hole, in 

 hole, in 

 hole, in 

 hole, in 

 hole, 7 

 hole, 7 

 hole, 7 

 hole, in 

 hole, a 

 hole, 7 



hole, in 

 hole, in 

 hole, in 

 hole, in 

 hole, in 

 hole, in 

 hole, in 

 hole, in 

 hole, in 



dust, 6 men sinking, 

 dust, 7 men sinking, 

 dust, 7 men sinking, 

 dust, 7 men sinking, 

 dust, 7 men sinking, 

 dust, 7 men sinking, 

 dust, 7 men sinking, 

 dust, 7 men sinking, 

 dust, 7 men sinking, 

 dust, 7 men sinking, 

 men sinking, 

 men sinking, 

 men sinking, 

 dust, 7 men sinking, 

 little gas escaping, 

 men sinking. 



dust, 7 

 dust, 7 

 dust, 6 

 dust, 7 

 dust, 7 

 dust, 7 

 dust, 7 

 dust, 7 

 dust, 7 



men sinking, 

 men sinking, 

 men sinking, 

 men sinking, 

 men sinking, 

 men sinking, 

 men sinking. 

 men sinking. 

 men sinking. 



120 yards down Engine Brow 

 Works. Standing. 



The increase of temperature with the depth, as exhibited in the preceding Table, 

 is shown graphically in Plate I. The in-egidarly curved line takes a com-se which 

 is approximately a mean of the results ; the straight line is that which shows the in- 

 crease of temperature on the assumption that it varies directly as the depth. 



On examining the Table or the diagi'am, it will be seen that the experiments in- 

 dicate some considerable irregularities ; nor is this greatly to be wondered at, if we 

 consider the diiEculties of the inquiry, and the liability to error in assuming the 

 temperature of a single bore-hole as the mean temperature of the stratiun. At the 

 same time it is not probable that the temperature in the mine shaft has in any 

 degree aifected the results, and we must therefore accept the observations as a whole, 

 and attempt to ascertain their general bearing. 



As to the rate of increase, they appear to confirm previous experiments, in which 

 it has been shown that the temperature increases directly as the depth. The rate 

 is at first rather less than this, afterwards somewhat greater, and at last again less ; 

 but, on the whole, as will be seen in the Plate, the straight line, on which the 

 temperature increases as the depth, nearly expresses the mean of the experiments. 

 The amoimt of increase indicated in these experiments is from 51° to 57J° as the 

 depth increases from 5f yards to 231 yards, or an increase of 1° in 99 feet. But if 

 we take the residts which are more reliable, namely, those" between the depths of 



