Page:Transactions NZ Institute Volume 15.djvu/473
The average of thirteen analyses of the true brown coals from this district give
| Fixed carbon | 42.87 |
| Hydro-carbon | 31.89 |
| Water | 20.40 |
| Ash | 4.84 |
| 100.00 |
as their composition, the fixed carbon varying from 49 to 38 per cent., and the water from 18 to 24 per cent. The coal from the different mines does not vary a great deal in character, for good and inferior samples can be obtained from each.
Besides that at the Malvern Hills, there are two seams of brown coal, each 10 feet thick, at the Rakaia Gorge, of which the average composition is—
| Fixed carbon | 45.76 |
| Hydro-carbon | 26.62 |
| Water | 18.71 |
| Ash | 8.91 |
| 100.00 |
and at Mount Somers a seam 25 feet thick occurs, having a composition of—
| Fixed carbon | 39.60 |
| Hydro-carbon | 39.20 |
| Water | 8.80 |
| Ash | 12.40 |
| 100.00 |
In Otago there are brown coals of an inferior character near Oamaru; at the Green Island near Dunedin; and several other localities in which small mines only have been opened to supply local demands.
The Green Island Mines, of which there are seven, are working seams of coal from 13 feet to 19 feet thick, and to a great extent supply Dunedin with household fuel. The coals have an average composition of
| Fixed carbon | 40.84 |
| Hydro-carbon | 36.57 |
| Water | 18.67 |
| Ash | 3.92 |
| 100.00 |