The shortage of coal rchich has recently been experienced in CUristehnreh and oth** parts of the colony, and which has been by no means of infrequent occurrence in the past, and may be experienced in the future, will, probably, have the effect of drawing the attention of coal-mine uwners to the im portance of the manufacture of bri quettes froni the unsaleable brown coal slack and from the slack of the soft bituminous coals found in parts of the West Coast. On this subject Mr J. Hayes, Inspecting Engineer to tihe Mines Depart ment, contributes an exhaustive article in his "Inspection of Coal Mines Report, an abstract of which appears in the August number of "The New Zealand idines "Re cord."

The question of the utilisation of coal slack, he writes, must sooner or later be taken into serious consideration. Und«r existing conditions there are several areas of soft bituminous coals in the West Coast mining district which cannot be worked except at considerable loss. This coal ap peass to have been severely crushed by A'ature's forces, and owing to" its very fri able character it wiU not stand the'ordi nary handling and transit without being smashed up into dust. That such coals can be worked up into valuable inel suit able for use in locomotives or steamships, as well as.for ordinary purposes, is evidenced by the fact that the slack produced at brown coal mines in parts of Continental Europe is manufactured into good briquettes, as is also tihe slack of the bituminous coal mines of England, America, and elsewhere. From information supplied by the manu facturers of the machinery required, Mr Hayes is able to give the following informa tion : —'Small coal, when necessary, is still further reduced by suitable grinding machi nery, then mixed at a fairly high tempera ture with coal tar, pitch, or other suit ably binding materia!. It is then run into moulds and subjected to heavy pressure, the result being a "briquette" of compressed fuel. It is claimed that tfliese briquettes are superior to lump coal, being really denser than the actual lump, and will burn from the outside thoroughly to the centre with out decrepitating (or exploding), under the heat; also that they will not disintegrate from atmospheric influences, and can be cleanly handled and stored compactly. 