local subterranean exhalations containing quicksilver, the formations of both pyrites and cinnabar may be readily explained.
Coal is found in many localities on the N. W. Coast of Borneo and crops up in the Sarawak Territory at Simunjan, at Lingga and other spots in the Batang Lupar district, in the Rejang, and in the Mukah and Bintulu rivers. It was formerly worked at Sadong, and the mine has recently been re-opened by the Government, and now supplies regularly a small quantity of fair steam coal. For the past two years an exploration of the Lingga seams has been in progress, and it is hoped that this field will be shortly worked on a large scale. The other outcrops of coal of importance are those of Mukah and Rejaug: both in such inaccessible situations as to be for the present quite useless, although, so far as is known, of good quality and considerable extent. The varieties of the mineral found are anthracite and cannel coal, both of which appear to be remarkably free from pyrites and sulphur. The Cannel coal has been found to give a very small percentage of ash (1.20 according to an analysis by Dr. Stenhouse) but this advantage is counterbalanced by the presence in it of considerably more Nitrogen than is generally exhibited by such coals. The ordinary Lingga coal is very nearly identical in composition, as regards the proportion of carbon and hydrogen, with the Hartley-Newcastle coals, as Dr. Steuhouse has lately shown by the following analyses conducted in duplicate.
| Carbon | Hydrogen | Sulphur | Oxygen & Nitrogen | Ash | |
| Sarawak Coal | 81.41 | 5.49 | 0.68 | 4.47 | 8.04 |
| S'wak Cannel Coal | 72.21 | 5.43 | 0.85 | 20.31 | 1.20 |
| W. Hartley Main | 81.85 | 5.29 | ... | ... | ... |
| Newcastle Hartley | 81.81 | 5.50 | ... | ... | ... |
It would be premature to take these analyses of small samples, however exact, as affording reliable data on which to base an opinion as to the value of the bulk of the Sarawak Coal. Nevertheless the trial of the Lingga coal lately conducted on board S. S. "Delhi" and Baroda" (Peninsula and Oriental Company), go rather to confirm, than to throw discredit on the laboratory analyses. Two 40-ton samples were burned under ordinary conditions of wind and speed, on board these vessels, and the coal was found with no more than the usual care from the stokers, to burn clearly with little smoke, and leave a residuum of only some 16 per cent in the furnaces, consisting of light and easily broken clinker. It would seem, however, that under severer test-conditions the coal would be found to burn a good deal faster than the best North Country Coals, uuless mixed with good ordinary steam-coal. I should add that
