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21 this Chair, premising that it will not be possible to include all or most of these in any single course.

A prominent place will be given to the consideration of the economic production and application of heat and light, with which nearly every industrial art, whether chemical or mechanical, is essentially connected. This will imply the discussion of the physical and chemical properties of the natural and artificial fuels— wood, peat, coal, coke, charcoal, the vegetable and animal oils, fats, waxes, and allied bodies; the processes of gas-making and candle-making; the structure of lamps, blow-pipes, fire-places and furnaces; the consumption of smoke, the removal of the noxious products of combustion, the ventilation and heating of apartments; the use of sulphur, phosphorus, and certain of the metals, as fuels; the preparation of coloured signal-lights; the production of self-lighting arrangements; the manufacture of lucifer-matches; the manufacture of gunpowder, gun-cotton, and other explosives.

The consideration of these subjects will require the discussion of several connected ones— as with the manufacture of wood-charcoal, that of wood-vinegar, wood-spirit, creosote; with gas-making, the manufacture of tar, pitch, pitch-oil, naphtha, and the salts of hartshorn; with candle-making, that of the fatty acids of glycerine, and perhaps the manufacture of soap. This episodical list, indeed, might be extended immensely.

A Second great division will be the economic development of electricity, and its application to the production of light, the manufacture of pigments and other chemical products, the casting of metals, and their reduction in special cases from artificial ores, the firing of mine-charges, the working of the telegraph, the construction of machines for the therapeutic employment of galvanism, and certain other uses.

A Third division, of more limited value, but at present of great and increasing interest, will be the economic applications of light, as employed in the different modifications of Photogenic Art. This has hitherto been more an object of interest as a Fine Art, than as an Industrial one; but every day is adding to its value as furnishing an infallible, incorruptible, and most faithful copyist; and as it is intended to employ it largely in furnishing drawings for the Industrial Museum, it will receive special consideration at my hands.

A Fourth great division will be that of metallurgy, including the