Building Stones.

As the building stones of Otago have been so ably described by Mr. W. Blair, C.E.,^† it will be unnecessary for me to do more than make a very few remarks on the subject.

Sandstones.—These are almost entirely confined to the Putataka and Waipara formations; the older rocks being too much jointed, and the newer ones seldom being hard enough for use. However there are a few exceptions among the ferruginous grits of the Oamaru formation, and the white hard sandstones (sarsen stones) of the lacrustine beds in the interior. Sandstones of good quality are found in the Horse Range in the Hokanui Hills, and between the Mataura and Catlin’s River, but although valuable locally, they are not likely to come into general use.

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Limestones.—The most important building stone in the Province is undoubtedly the Oamaru limestone. Its beautiful color, and ease of working, combined with its hardening on exposure, make it a most valuable building material. The absorbent nature of this stone naturally throws a doubt on its capability of resisting the action of the atmosphere of a town; but hitherto the oldest buildings of it in Dunedin have not suffered in the least from this cause, except by loss of color. This stone is exactly similar to the limestone of Malta, of which the town of Valetta is built. Many of the buildings [gap — reason: illegible] town are of very great age, and show no sign of deterioration, although those portions of the fortifications that are exposed to the spray of the sea are very much decomposed.

Bluestones.—This is the name applied in the Colony to all kinds of volcanic rocks used in building. These are generally either trachyte breccia, or basalt. The former, which when good, is decidedly superior to basalt both in color and durability, is only found in the neighborhood of Dunedin Harbour. Very excellent quarries are opened both at Port Chalmers and Dunedin, and it is used largely in Dunedin for all the more substantial buildings. Basalt is found in many parts of the Province as well as near Dunedin, and will in time no doubt be more extensively used than at present.

Granite, &c.—Large quantities of granite are found in Preservation and Chalky Inlets, but it is very coarse grained, and probably, therefore, liable to decomposition, and except for inside pillars, for which purpose its color is well suited, I do not think that it would be a safe stone to trust to. The whole of the other West Coast Sounds seem remarkably bare of good building stone in sufficien[gap — reason: illegible] quantities for use; but the syenite of the Bluff Hill is of excellent quality, and far superior to anything on the West Coast. It is also more accessible for working. Good syenite will no doubt also be found at Stewart Island, but I do not know of a locality for it, all the eruptive rocks that I have seen from there being very coarse grained.