31

H.—44a

(vi) Depreciation and Sinking-fund Charges. Table 24.—Expenditure per Ton Output on Depreciation and Sinking Funds of Coal-mines, 1913-18.

Comparison, of the figures given in the above table is rendered almost impossible by the fact that the companies make provision for depreciation only as the condition of their balances allow, and seldom follow any other fixed principle in assessing this allowance. There have been decreases during the period in respect of some collieries, but this, except in one case, does not imply that the cost is actually decreasing, but only that it has not been fully allowed for. The highest costs are in the case of the State mines, where adequate allowances have been made. 5. RELATION OF LOST TIME TO COST OF PRODUCTION AND OUTPUT. (i.) Classification of Lost Time. Among the causes of both the high cost of production and the increase in that cost during the period a prominent place was assigned by some of the mine owners and managers to the amount of time voluntarily lost by the miners. If such lost time could be diminished there would be not only a lower cost per ton, but a greater output, both results tending to lower the price of coal to the consumer. The cost of production per ton falls the nearer the full working-limit of a mine is reached. If all the working-places were fully manned at every shift worked by the mine the cost of production per ton would approach the minimum possible at that time, since all standing charges would be spread over the maximum possible output. Conversely, the further the departure from the limit of full working the higher the per ton mining-cost. The average number of shifts worked (or lost) per miner per week is therefore an important factor in determining the cost of production. In this connection it is necessary to draw certain distinctions. There is, in the first place, the number of shifts (or days) per year worked by the mine. This varies from time to time, as well as from mine to mine, according to such factors as weather (particularly in localities subject to floods and those dependent upon bar harbours for shipping-facilities) and-the degree of industrial peace or unrest. When a mine is " idle " only certain shift-men are employed in and about it. In the next place, there is the average number of shifts worked per week by the miner expressed as a percentage of the number of shifts worked by the mine itself. In regard to this latter figure we must further distinguish between the absolute amount of time lost — i.e., the difference between the number of times the mine was open and the average number of shifts worked per miner—and any increase or decrease in that amount during the war period, since a. certain amount of absence may be a necessary condition of the miner's health and maximum efficiency, and that amount may not have been realized at a given time within the period. (ii.) Average Percentage of Possible Shifts lost by Miners. General statements in evidence assessed, the time lost by miners at about 10 per cent, of the possible working-time, and alleged that it had shown an increasing tendency during war-time. Analysis of. the mine-records supported these statements in many cases, though in some the position showed improvement since 1914. At one large mine the percentage of time lost had nearly doubled between 1913 and 1918, as shown in the following table: —

Table 25.

Mine. 1913. 1914. 1915. 1916. 1917. 1918. Increase or Decrease. .tt. . . B s. d. 0 9-93 0 11-2 0 1-34 s. d. 0 10-32 1 0-84 0 5-63 s. d. 0 10-27 0 6-41 0 3-72 s. d. 0 9-82 0 6-77 0 103 0 5-6 1 7-49 1 2 s. d. 1 0-88 0 4-32 0 1-51 0 5-5 1 3-95 0 4-95 s. d. 1 6-69 s. d. 0 8-76 0 11-20 0 0-13 0 l-3f 0 8-41 1 2-02f 0 7-13f 0 5-33 0 2-071 0 2-2f 0 2-1 C D 1 10-82 1 8-03 0 1-47 0 4-3 2 7-23 0 0-29 E* .. 1 2-31 0 7-13 0 6-04 1 8-99 JiF* .. rj" G 0 3-54 0 7-18 0 11-2 0 6-2 0 8-28 0 6'23 0 6-5 0 9-85 0 7-64 1 2-35 0 11-37 0 5-11 0 9 0 8-3 H I T 0 7-6 0 7-15 0 8-8 0 5-22 (Feb., 1918) 0 5-78 K (Feb.-Aug., 1918) 0 4-86 L 0 4-86 Highest Lowest 1 2-31 1 8-99 1 10-82 1 7-49 1 3-95 2 7-23 0 8-76 1 2-02f •State lines. Decrease.

Year. .913-14 917-18 Po 31st March, 1918 .. i.pril to August, 1918 .. Percentage of Possible Percentage lost. Shifts worked. 93-38 6-61 90-45 9-54 90-07 9-91 87-69 12-30 Lost by Accident. 4-47 5-36 4-41 4-38 Lost otherwise. 2-13 4-17 5-49 7-87 Ilemarks. Omitting strike-time. Equal to about 7,000 tons of coal.