C—2

51

Table showing an Analysis of the Ventilation in the Principal Collieries of the Dominion made by the Chief Inspector during the early part of 1920 — continued.

Name of Colliery. Place of Observation. Date. Quantity of Air passing per Minute. fe<i tH^ 3% > S3 > fc i & Analysis of such Return r, ... s ,. Air bv Dominion Quantity of Air Analyst, per Person per ' Minute.* Remarks. I I CO 2 . Oxygen. CH 4 . Oxygen. CH 4 . South Island —contd. Blackball .. No. 1, rise section, return No. 3, dip section, return Main return at fan Nos. 1 and 2, dip section, return No. 4, west section, return Evans section return South-east pillars return Nos. 2 and 4 sections return Wareatea jig section return Cascade section return Main return at fan Kruger's dip return Dip section return Mundy r 's and No. 6 dip return .. Main return at fan Fred's seam return 18 ft. seam return 6 ft. seam return Main return at fan No. 3 dip return Main return No. 1 section return No. 2 section return Small seam intake or return 3/2/20 3/2/20 3/2/20 10/2/20 9/2/20 10/2/20 10/2/20 11/2/20 24/5/20 24/5/20 24/5/20 13/2/20 7/1/20 8/1/20 8/1/20 9/1/20 9/1/20 9/1/20 9/1/20 12/1/20 15/1/20 15 1 20 15/1/20 13 1 2ii Cub. ft. 8,085 11.795 42,120 15,730 16,626 7,614 Unappreciable 19,800 10,810 6,302 97,643 2,142 6,288 14,297 22,542 3,226 Unappreciable 7.047 27,360 6,864 6,547 1,980 6,528 Unappreciable 16 28 Cub. ft, 505 421 346* 494 467 Per Cent. 051 0 35 007 Per Per Cent. Cent, t 20 33 20-54 20-81 t 20 70 < .. 20-90 20-85 : .. |. 20-04 2000 1948 0-37 20 16 0-35 20-62 .. I 20-70 .. } 20-60 ' .. ) 20-68 .. J 20-70 20 69 t 20-63 t Millerton 42 30 15 10 66 40 22 2 Air short-circuited. 1 1 3 4 2 0 14 Westport-Stockton .. Coalbrookdale Unapnreciable 273 230 233 007 014 Water-gauge, 2-5in. at 10ft. fan; air short-circuited through leaking stoppings; effective ventilation, 17 per cent. Inadequate quantity. Ironbridge Taratu Kaitangata No. 1 . . 12 38 43 1 128 165 304 038 0 30 0-47 0-42 0 13 0 10 0 13 019 019 005 2 Effective ventilation 63 per cent. Air short-circuited through leaking stoppings before it could reach first miner. Only 37 per cent, of the air passed through workings owing to leakage. Kaitangata No. 2 10 10 31 1 1 263 Unappreciable 227 Nightcaps .. , Jubilee Saddle Hill 18 17 9 15 7 i i 348 350 220 395 i 0-28 • Wairio Unappreciable No pretence at any system of ventilation. Air stagnant in this seam. * The quantity of air per person is obtained by dividing the total quantity circulating, after an allowance of 600 ft. per horse has been deducted. t No sample taken; the mine-air was obviously wholesome.