But more widely useful still in relation to vegetable and animal life is the property which water possesses of dissolving and rendering fluid a host of usually solid bodies. Put sugar or salt into water, it disappears and becomes fluid and penetrative like the water itself. The salt sea contains within its bosom many substances so dissolved; the fluids that circulate through our veins are chiefly water holding various compound bodies in solution; the moisture which the plant-root drinks in carries with it into root, stem, and leaf many substances it has taken up from the soil; and the purest waters we consume for domestic use are not free from foreign matters of mineral and organic origin. In all this there is a purpose, and good flows to all living things from this solvent power of water.

It must suffice at present to mention one general benefit. Into the composition of the plant a variety of solid mineral substances enter, which it is the duty of the plant root to draw from the soil. In their solid form these substances could neither move freely through the soil nor find their way into the fine pores of the little rootlets. But dissolved in water they move as freely as the liquid itself, and penetrate with it into the most delicate tissues of plant or animal. Thus along the finest vessels they ascend through stem and twig and leaf, and distribute themselves wherever their presence is required.

It is so also with the animal. Into all its parts, solid saline, and mineral, matters enter as a necessary portion of their substance. These we introduce into the stomach along with our other food, but water must dissolve them there and make them fluid before they can find their way into the blood and be afterwards conveyed to the parts of the body where their several services are required. And here comes into view a glimpse of wise beneficence in what at first sight appears only a form of material evil. The impurities, as we call them, of natural waters are often of real advantage to those who drink them, supplying saline and mineral matters in which the food is deficient, or which the peculiar nature of the staple form of diet in a given region renders grateful to the enfeebled frame. The purest waters, therefore, are by no means to be considered as everywhere and in all cases the most wholesome. The natural waters of every locality are more or less medicated, so to speak, and the constitutions of the inhabitants by long use become adapted to their peculiar quality, and even their food is adjusted to it; so that to change their wonted beverage even for one more pure may sensibly affect the health, for years to come, of large masses of people.

Look next at the food we eat. This is either of vegetable or

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of animal origin, and what modern chemistry tells us regarding it is not only full of rich uses and of deep personal interest to every one of us, but is in itself truly marvellous. For, first, it abolishes the artificial distinction which mere sense has long established between animal food and vegetable food. The bread we simply bake is no longer quite different in use and quality from the flesh meats on which learned cooks exhaust their culinary skill. In bread we actually eat the substance of beef, and in bread and butter another form of that marbled flesh on which the eye of the epicure so placidly rests. In every variety of eatable plant there exists a proportion of what chemists call gluten, which is nearly identical with the muscular part of animal flesh, and a proportion also of fat, which is absolutely identical with the fat of animals. How unphilosophical and vain, therefore, the discipline which enjoins and makes a merit of abstaining from a substance when obtained from the body of an animal, and yet allows the use of the same substance when obtained from a vegetable!

Again, it shows us how curiously and by what admirable contrivances this food is prepared for man. Of carbon and nitrogen, such as float in the air, combined with the oxygen and hydrogen gases already spoken of, the flesh and tissues of animals, and the solid portions of vegetables in great part consist. But of these only one, the oxygen, serves directly as food either to animal or to plant. The plant, as we have seen, sucks in at times oxygen by its leaves, and some of this oxygen, no doubt, contributes to the formation of its growing substance. The animal, also, draws in oxygen from the air by its lungs, and uses it directly to build up the tissues of its body. Thus both animals and plants, to a certain small extent, feed upon raw and unchanged oxygen. But neither plant nor animal can so consume or work up elementary or uncombined hydrogen, nitrogen, or carbon.

And here, in pursuing further our inquiries in regard to the way in which they are respectively fed, a great difference at once presents itself between the plant and the animal; while, at the same time, a close and predetermined relation is seen evidently to exist between them.

It would be out of place here minutely to discuss the way in which plants and animals are nourished and sustained. It is sufficient to observe, that throughout what may be called dead or mineral nature there exist numerous, more or less simple, compounds of hydrogen, carbon, and nitrogen, which the plant is able to appropriate and employ in building up its growing

substance. In the air, for example, there floats, as we have seen, an unfailing supply of carbonic acid. The same gas exists also in nearly all natural waters, and in the soil it is formed abundantly along with other comparatively simple combinations of carbon. All these the plant takes in by its leaves or by its roots, and from them, by a still obscure chemistry, extracts and makes its own the carbon they contain. So from water and ammonia it takes hydrogen-from nitric acid, ammonia, and other compounds, it takes nitrogen- and from the dead earthy matter of rocks and soils it selects and takes up the so-called incombustible, inorganic, or mineral ingredients which are necessary to the production of its perfect substance.

Of raw and simple materials like these, the animal can make nothing. Among them all, water is the only one it can with safety introduce into its stomach, and upon this it cannot live or be sustained. It is upon the results of the plant's labours-upon the substances of the plant's body, the new and usually more complex combinations which the living plant has manufactured from the simpler compounds which nature presents to it that the herbivorous animal can alone support itself. Out of these, by wonderful methods, which we cannot explain, the plant forms starch, sugar, fat, and gluten, in all their varieties. So formed by the plant, the animal eats them; digests and changes them anew by a further mysterious chemistry which we are only now beginning faintly to follow; and finally fits them into appropriate places in its own body. Thus dead nature daily labours for the food of plants; the living plant daily labours for the food of animals. In the order of nature, the plant must precede, and accompany, and unceasingly work for the animal. Alone, in the midst of physical nature, man and all other animals would be helpless, forlorn, and short-lived.

Thus far, then, our science teaches us how different in relation to external things the life of plants is from the life of animals, and yet how closely and inseparably they are connected; - how selected first from earth and air to form the plant, the same matter next builds up the more curious animal frame; and when that is worn out, or dies, returns again to earth and air, to run the same course anew. It thus shows one simple though grand idea pervading all life, embodied in the existing course of animated nature, yet by its manifold and complex details, leading us perpetually to admire the surpassing Workman from whose beneficent intellect it sprung.

And this plant, so essential to the life of all, what a miracle of chemical contrivance and chemical endowment it is! This

little sporule, which the unassisted eye can scarcely discern,— in which even by the aid of the microscope only an obscure structure can be observed-in this little germ how much discernment and concealed intention really rests! Placed in one condition, it remains unalterably the same for an indefinite period of time. If life is there, it is life in a state of quiescent torpor ; quiescent yet watchful; a life of most profound repose. Placed in another condition, it seems at once to perceive the change. It swells and moves; the inner being bursts its shell, and comes forth; slowly and cautiously expands its growing length; feels, as it were, and examines every substance it touches; selects and rejects as suits its purpose; transforms each chemical body it takes up, and fits it for the place it is intended to occupy in the building about to be erected; and with materials so collected and prepared, it builds unceasingly-without wearying, and after a predetermined plan-green leaf, graceful twig, towering stem, blooming flower, luscious fruit, nourishing seed; till through the wonderful working, mechanical and chemical, of that hidden speck of life which so long slept in the microscopic germ, beauty and grace adorn the landscape, and inert useless matter has been abundantly converted into food for man. How slow and limited is our most advanced chemical knowledge, compared with that easy skill so richly given to this tiny seedlet!

Let us leave now those substances which are naturally necessary to human life, and consider for a little those things which by habit have become to modern nations a kind of second nature. In looking to modern life in this point of view, it appears widely distinguished not only from that of classic times, but even from that of the middle ages. Sugár, tea, coffee, cocoa, brandy, and tobacco have all become familiar to Christian Europe and America within the last 300 years. By the end of the 14th century, the cultivation of sugar had already become important in Western Asia and Northern Africa. Brought into Spain by the Moors, and cultivated in Andalusia, it was planted in the Madeiras by the Portuguese, who in 1520 possessed already sixty sugar manufactories in the island of St. Thomas alone. Thence it penetrated to America with the Spaniards, and became a staple article of Spanish American growth. Now, about 4500 millions of pounds of cane sugar, produced chiefly in America, pass yearly through the hands of European and American merchants, while in addition nearly 500 millions of the same kind of sugar are extracted from the beet-root in Northern Europe, and consumed in the different countries of our more eastern continent. It was not till

the year 1659 that sugar refining began to be practised in England; and in 1700, the consumption of all England was only 20 millions of pounds. Now, we are not only the great refiners of Europe, but by far the largest consumers of sugar of every variety. In the year 1853, the consumption of the United Kingdom amounted to 818 millions of pounds of sugar, being at the rate of 28 lbs. a year-upwards of half-a-pound a week-for each of our population. What a change in the habits and modes of living of the people does this imply!

The introduction and rapid spread of the habit of using tea is still more recent and remarkable. The leaf was not brought to Europe till about the beginning of the 17th century. Sugar refineries were already in operation in England, when in 1664 the East India Company thought a couple of pounds of tea a not unroyal gift to present to the Queen of England. Now we consume at the rate of two pounds a head as the yearly allowance of every individual in the three kingdoms, and the total annual consumption of the United Kingdom is about 25,000 tons, or sixty millions of pounds! The use of this leaf is specially great in China and Thibet, in Russia, Holland, and England, and in the states and provinces of North America. The entire quantity consumed over this wide area, among about 500 millions of men, is roughly estimated at upwards of two thousand millions of pounds.

Coffee, though less a favourite among us than tea, is preferred to it by several of our Continental neighbours. On the whole, perhaps the spread of coffee drinking during the last 300 years has been more wonderful even than that of tea. It was not till the beginning of the 15th century that it was introduced into Arabia from Abyssinia. About the middle of the sixteenth, it began to be used in Constantinople, and in spite of the opposition of priests and Turkish doctors, it may now be considered as the staple minor luxury of Mahomedan life. In the middle of the 17th century (1652), the first coffee-house was opened in London; and now, two hundred years after, the yearly consumption of coffee in the United Kingdom has reached the large amount of 35 millions of pounds. The quantity of the coffee bean actually bought and sold is about 600 millions of pounds every year, and it is in daily use among perhaps 120 millions of men!

We may pass briefly over cocoa, the ancient beverage and nutriment of the Mexican Incas, and still the favourite in modern times of Central America, of Italy, and of Spain. It is consumed to the extent of about 100 millions of pounds a year, and among 50 millions of men.