As a means of supplying fuel, without which man must remain constantly in the savage state, wood is of inestimable value. In the process of combustion, the elements of the trees enter into new combinations, evolving both light and heat, which at once maintain life and render it a state of enjoyment and usefulness. For this purpose in Britain, we chiefly employ fossil fuel, stored up in the secret places of the earth, and, therefore, we attach less importance to recent wood; but other parts of the world are not so favourably situated, and to the inhabitants of these places fresh, or but lately felled, wood is necessary for their existence. Even in France, though partially possessed of coal, it is estimated that the quantity of wood employed to supply heat, whether for comfort, cooking, or in manufactures which require a high temperature, amounts to seven-tenths of the entire consumption. The superiority of wood fuel, whether fossil or recent, over every other material resorted to with a like intention, shall be shown in a subsequent part of this paper. I therefore pass on at present to demonstrate the utility of vegetable substances in affording the means of subsistence to man and animals. In the observations I am about to make, it is impossible to avoid anticipating some of the remarks which belong to the subject of fruits and seeds as articles of food, since the same principles of nutriment are found in the stems of certain plants as are deposited in the fruits or seeds of others.