4. Machinery.

Of the New Zealand coal-mines, only twenty-five in 1891 utilized engine-power for raising the mineral, and this is accounted for by the fact that so much outcrop coal is found level-Free, and at present horsta or hand-power is usually found sufficient. In a few cases good winding and hauling-engines are employed. As regards ventilation, it appears that there are three fans, five furnaces, one steam-jet, one steam-jet and furnace combined, while two mines owe their ventilation to steam-pipes in the upcast shaft. Compressed air is occasionally, but seldom, employed; electricity as a motive power in the one case already noted. Electric signals are common. A Harrison coal-cutter was tried at Kaitanguta, where also power rock-drills were very successfully introduced. Mechanical stokers were tried at Greymonth and abandoned. Telephones are very largely utilized.