and vast extents of mountain districts in Africa, America, Asia, and Australia, which at present yield no products to commerce, and are too barren to support higher vegetation, might furnish an unlimited supply of lichens useful in dyeing. The vast continents of India and neighbouring countries and islands, for instance, already promise valuable results in this respect." The re-introduction of the former trade in cudbear, I may add, would furnish remunerative employment to many of the inhabitants of the Highlands, who have within the last few years been deprived of another source of comfortable subsistence, by the discovery of barilla as a more efficient substitute for the kelp, which they used to gather in immense quantities on the western coasts and islands, and sell to the soap-manufacturers, and who are now compelled by poverty and want of work to leave their native land, and seek their living on foreign shores.

I cannot conclude this chapter more appropriately, than by quoting the following eloquent remarks made by Ruskin, in his last volume of Modern Painters, which also apply conjunctly to the subjects of the preceding chapter: "Meek creatures! the first mercy of the earth, veiling with hushed softness its dentless rocks; creatures full of pity covering with strange and tender honour the scarred disgrace of ruin, laying quiet finger on the trembling stones to teach them rest. No words that I know of will say what these mosses are; none are delicate enough, none perfect enough, none rich enough. How is one to tell of the rounded bosses of furred and beaming green, the starred divisions of rubied bloom, fine

filmed as if the rock spirits could spin porphyry as we do glass; the traceries of intricate silver and fringes of amber, lustrous arborescent, burnished through every fibre into fitful brightness, and glossy traverses of silken change, yet all subdued and pensive, and framed for simplest, sweetest offices of grace. They will not be gathered like the flowers, for chaplet or love-token; but of these the wild-bird will make its nest, and the wearied child its pillow. And as the earth's first mercy, so they are its last gift to us. When all other service is vain from plant and tree, the soft mosses and grey lichens take up their watch by the headstone. The woods, the blossoms, the gift-bearing grasses have done their parts for a time; but these do service for ever. Trees for the builder's yard, flowers for the bride's chamber, corn for the granary, moss for the grave."

CHAPTER III.

FRESH-WATER ALGE.

"Books in the running brooks."

"And plants of fibres fine as silkworm's thread,
Yea, beautiful as mermaid's golden hair
Upon the waves dispread."

SOUTHEY.

"IF the Author of Nature be great in great things, he is exceedingly great in small things," was the paradoxical remark of Rousseau, the deep meaning and truthful application of which, the world at the present day is just beginning to perceive. Everywhere, we find that microscopic life performs a work of inconceivable magnitude and importance; that the humblest and meanest organisms, though all unseen and unmarked by the ordinary senses of man, modify, by the mere force of untold numbers, the appearance of the earth, and contribute more to the formation of its grandest features than the great visible agencies around us. It was not, for instance, by Titanic forces that the island world of the Pacific was raised from the immense depths of the ocean, but by zoophytes so minute that the foot-tread of a child could crush thousands of them into atoms. The chalk cliffs of southern England, which form a stupendous barrier to the wild

fury of the German and Atlantic oceans; the limestone rocks, of which immense tracts of country are almost entirely composed,-were not formed by the gigantic remains of megatheriums, mastodons, and other extinct monsters, which lived and died amidst the wildest convulsions of a nascent world, but by the shields and shells of inconceivable myriads of organisms, to each individual of which, the stage-plate of the microscope would be as large a field for its gambols, as a whole country would be to one man. It is not by the hurricane or the furious storm that our fairest orchards and most luxuriant fields are laid waste, and converted into wildernesses of skeleton leaves, and blackened and withered stalks, but by the ravages of the tiniest insects, and the minutest and most contemptible fungi.

In these days of popular science, when the most abstruse subjects come to us in forms as light and easy as the whisperings of confidential friends, or the chit-chat of the family circle, no department of natural history is more extensively and successfully studied, than that which relates to the algae or sea-weeds. And this need not excite surprise, for there is no class of plants more interesting, whether we regard the beauty and splendour of their colours, the elegance and variety of their forms, or the romantic situations in which they occur. The invention of that elegant ornament of the parlour and drawing-room, the aquarium, now so popular, has afforded great facilities for the study of these plants, under conditions and circumstances closely analogous to those of their native haunts; and much insight has in consequence been obtained into their functions and habits,

It

which would otherwise either remain in obscurity, or be revealed only by the "chance fortune of the hour." would be interesting to state some of the novel facts thus elicited; but I must forbear, as our attention in this chapter, is to be occupied with the history of an important and remarkable division of the algae called hydrophites, or fresh-water alga, whose economy is altogether peculiar, and whose forms are widely different from the lovely Plocamiums and Delesserias, which we frequently observe with admiration in our wanderings along the sea-shore.

There is a peculiar charm about the fresh-water algæ, derived from the nature of the element in which they live. Aquatic plants of all kinds are more interesting than land plants. Water is so bright, so pure, so transparent, so fit an emblem of that spiritual element in which our souls should bathe and be strengthened, from which they should drink and be satisfied. It is a perpetual baptism of refreshment to the mind and senses. It idealizes every object in it and around it; the commonest and most vulgar scenes, reflected in its clear mirror, are pictorial and romantic. It is ever varying in its unity, so that the eye never wearies in gazing upon it. All these associations invest the confervæ which flourish in it with a peculiar nameless interest, independent of their own mysteries of structure and function. They mingle, like vegetable lotos-eaters, with the snow-white chalices and broad velvet leaves of the lilies, in the tranquil shallows of the moorland lake; and, with the golden hues of the sunset, and the rosy blush of the heather-hills around, create a scene of enchantment in the clear pellucid depths.