pure oxygen gas. And thus, day after day, lasts, it cannot render the atmosphere unthe leafy labor proceeds, and by the aid of wholesome to animal life. To the knowledge the raw materials which the working mouths of these and many similar adjustments, the thus incessantly carry out and in, other vital study of the chemistry of the air we breathe parts within the plant produce the varied forms has gradually led us.

of matter of which the vegetable substance con- Turn now to the water we drink. In this sists. The solid stem is formed, as it were, admirable fluid, so clear, so bright, so grateful of compressed and hardened air; and vast for- to the system, so healthful to the temperate, ests on a thousand hills thus steal from the so necessary to all,-the delight of Grecian atmosphere the carbonaceous matter of which song,-the charm of the Eastern paradise,— they mainly consist. of this fluid, lauded with justice by the phyBut a marvel of wondrous forethought dis-siologist, and worshipped, not unduly, by the closes itself as we interrogate more nearly this total abstainer,-chemistry tells us that threemutual relation between terrestrial plant-life fourths of our apparently solid bodies consist, and the air which surrounds it. The quantity and that it forms nearly as large a proportion of carbon in the air, as we have seen, is small; of all living vegetables during the height and -some thirty odd grains over every square vigor of their growth. In this fluid, looked inch. The active growth of vegetable matter upon as elementary till nearly our own times, over the entire surface of the globe, is able to modern research has taught us to see the result convert the whole of this carbon into the sub- of a subtle union between the oxygen we have stance of solid wood within the lifetime of a spoken of, and another gas, to which the name single generation of men. But hundreds of of hydrogen (water-former) has been given. generations of men have already lived on the Kindle this latter gas in the air, and it burns earth, and thousands of generations of other with a pale flame. Hold a cold bell glass over animals before him, yet carbon is as abundant the flame, and its under surface will become in the atmosphere as ever, and vegetable bedewed with moisture, and drops of water growth, in similar circumstances, quite as lux- will trickle down its sides. Collect this water uriant. There must, therefore, be some nat- and submit it to a current of electricity; the ural sources of supply from which carbonic liquid will disappear, and in its stead the two acid gas flows into the air, as fast as the leafy gases oxygen and hydrogen will remain. These mouths withdraw it. These sources, also, experiments prove, first, that while burning in must be watched and regulated, that they the air, the hydrogen unites with the oxygen may not pour it in so fast as to increase unduly of the atmosphere and forms water; and, the natural proportion of this poisonous gas second, that the water thus formed consists of in an atmosphere which man and countless these two gaseous constituents only, compressother animals perpetually breathe. These sev-ed and bound together by some incompreheneral conditions are beautifully fulfilled by a sible connexion, which it makes us no wiser to series of compensating natural operations, call chemical combination. which, like the growth of plants, form a part It is, indeed, incomprehensible how water, of the existing system of things; and, like it, the enemy of fire, should itself consist of two never cease to proceed at a duly measured gases, the one of which burns most readily, pace. while the other is the great natural supporter Thus, plants die, and the carbon of their of living fire. And it is equally strange that stems and leaves is gradually resolved again oxygen, so indispensable to animal life, should into carbonic acid by the gradual progress of form eight-ninths by weight of a liquid in which decay, or by the quicker agency of fire. Or few terrestrial animals can live for more than the plant is eaten by the living animal, and two or three seconds of time. By no known after many chemical changes within the ani- theory of physical or mechanical union can we mal's body, its carbon is breathed forth again satisfactorily explain how properties so new from the lungs and skin in the form of car- should be the result of such chemical combibonic acid. In these several ways the very nations.

same carbon which the plant-leaf has taken The chemical study of this water in its refrom the air, is again, in a great measure, re-lations to animal and vegetable life presents turned to it. A certain small and indefinite new points of interest. The most important proportion of their carbon is indeed yearly of its chemical properties are so familiar to us buried in the soil, or covered up in the depths that we rarely think of them, and certainly do of the sea, or accumulated in bogs and dismal not sufficiently prize them. Pure water has swamps. But to make up for this, the earth neither taste, nor smell, nor pungency. It is itself, from bubbling springs, from myriads of neither sour like vinegar, nor sweet like sugar, unseen fissures, and from the open mouths nor alkaline like soda. It irritates no nerve of of many volcanoes pours forth a ceaseless con- sensation, even the most delicate, nor is the tribution of carbonic acid gas, ceaseless, yet in tenderest part of the animal frame disturbed such wise limited, that so long as vegetation by contact with this universal fluid. It is thus

fitted to penetrate unfelt into the subtlest tis- make them fluid before they can find their way sues, and without causing the slightest jar to into the blood and be afterwards conveyed to flow along the finest, most sensitive, and most the parts of the body where their several serhair-like vessels. It soothes and assuages vices are required. And here comes into view wherever it comes, lessening inflammation, lul- a glimpse of wise beneficence in what at first ling pain, diluting unhealthy fluids within the sight appears only a form of material evil. The body, and washing morbid humors and waste impurities, as we call them, of natural waters are materials from the sickly and changing frame. often of real advantage to those who drink them, Again, as a cooling agent water is equally in- supplying saline and mineral matters in which valuable. In a dry and thirsty land we feel and the food is deficient, or which the peculiar acknowledge the pleasure of bathing our heated nature of the staple form of diet in a given region bodies in the sea or the running stream. But we renders grateful to the enfeebled frame. The are less sensible how it watches over us, as it purest waters, therefore, are by no means to be were, every passing moment, dispelling each considered as everywhere and in all cases the rising heat, and removing from the body every most wholesome. The natural waters of every excess of warmth which might disturb the locality are more or less medicated, so to speak, equable working of its many parts. Do we eat and the constitutions of the inhabitants by long inflammatory food, or drink over-stimulating use becomes adapted to their peculiar quality, fluids, the excess of bodily warmth produced and even their food is adjusted to it; so that to converts a portion of water into vapor, and the change their wonted beverage even for one lungs throw it off into the air. Do we by hard more pure may sensibly affect the health, for labor, or other usual exertion, exalt the temper-years to come, of large masses of people. ature of the body, the same water again takes up Look next at the food we eat. This is either the superfluous heat, and bathing in perspiration of vegetable or of animal origin, and what modboth skin and lungs restrains with due bounds the ern chemistry tells us regarding it is not only growing inflammation. full of rich uses and of deep personal interest to But more widely useful still in relation to every one of us, but is in itself truly marvellous. vegetable and animal life is the property which For, first, it abolishes the artificial distinction water possesses of dissolving and rendering fluid which mere sense has long established between a host of usually solid bodies. Put sugar or animal food and vegetable food. The bread we salt into water, it disappears and becomes fluid simply bake is no longer quite different in use and penetrative like water itself. The salt sea and quality from the flesh meats on which learncontains within its bosom many substances so ed cooks exhaust their culinary skill. In bread dissolved; the fluids that circulate through our we actually eat the substance of beef, and in veins are chiefly water, holding various com- bread and butter another form of that marbled pound bodies in solution; the moisture which flesh on which the eye of the epicure so placidly the plant-root drinks in carries with it into rests. In every variety of eatable plant there root, stem, and leaf many substances it has taken exists a portion of what chemists call gluten, up from the soil; and the purest waters we which is nearly identical with the muscular part consume for domestic use are not free from of animal flesh, and a proportion also of fat, foreign matters of mineral and organic origin. which is absolutely identical with the fat of In all this there is a purpose, and good flows to animals. How unphilosophical and vain, thereall living things from this solvent power of fore, the discipline which enjoins and makes a merit of abstaining from a substance when ob

water.

It must suffice at present to mention one tained from the body of an animal, and yet general benefit. Into the composition of the allows the use of the same substance when obplant a variety of solid mineral substances enter, tained from a vegetable !

which it is the duty of the plant root to draw Again, it shows us how curiously and by from the soil. In their solid form these sub- what admirable contrivances this food is preparstances could neither move freely through the ed for man. Of carbon and nitrogen, such as soil nor find their way into the fine pores of the float in the air, combined with the oxygen and little rootlets. But dissolved in water they hydrogen gases already spoken of, the flesh and move as freely as the liquid itself, and penetrate tissues of animals, and the solid portions of with it into the most delicate tissues of plant or vegetables in great part consist. But of these animal. Thus along the finest vessels they only one, the oxygen, serves directly as food ascend through stem and twig and leaf, and dis- either to animal or to plant. The plant, as we tribute themselves wherever their presence is have seen, sucks in at times oxygen by leaves, required. and some of this oxygen, no doubt, contributes

It is so also with the animal. Into all its parts, to the formation of its growing substance. The solid saline, and mineral, matters enter as a animal, also, draws in oxygen from the air by necessary portion of their substance. These we its lungs, and uses it directly to build up the introduce into the stomach along with our other tissues of its body. Thus both animals and food, but water must dissolve them there and plants, to a certain small extent, feed upon raw

and unchanged oxygen. But neither plant nor closely and inseparably they are connected;animal can so consume or work up elementary how selected first from earth and air to form or uncombined hydrogen, nitrogen, or car- the plant, the same matter next builds up the bon. more curious animal frame; and when that is And here, in pursuing further our inquiries in worn out, or dies, returns again to earth and air, regard to the way in which they are respectively to run the same course anew. It thus shows fed, a great difference at once presents itself one simple though grand idea pervading all life, between the plant and the animal; while, at the embodied in the existing course of animated same time, a close and predetermined relation is seen evidently to exist between them.

nature, yet by its manifold and complex details, leading us perpetually to admire the surpassing Workman from whose beneficent intellect it

sprung.

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 ob- And in this plant, so essential to the life of serve, that throughout what may be called dead all, what a miracle of chemical contrivance or mineral nature there exist numerous, more and chemical endowment it is! This little or less simple, compounds of hydrogen, carbon, sporule, which the unassisted eye can scarcely and nitrogen, which the plant is able to appro- discern,-in which even by the aid of the micpriate and employ in building up its growing roscope only an obscure structure can be observsubstance. In the air, for example, there floats, ed-in this little germ how much discernment as we have seen, an unfailing supply of carbonic and concealed intention really rests! Placed in acid. The same gas exists also in nearly all one condition, it remains unalterably the same natural waters, and in the soil it is formed for an indefinite period of time. If life is there, abundantly along with other comparatively sim- it is life in a state of quiescent torpor; quiescent ple combinations of carbon. All these the plant yet watchful; a life of most profound repose. takes in by its leaves or by its roots, and from Placed in another condition, it seems at once to them, by a still obscure chemistry, extracts and perceive the change. It swells and moves; makes its own the carbon they contain. So the inner being bursts its shell, and comes from water and ammonia it takes hydrogen-forth; slowly and cautiously expands its growfrom nitric acid, ammonia, and other compounds, ing length; feels, as it were, and examines it takes nitrogen-and from the dead earthy every substance it, touches; selects and rejects matter of rocks and soils it selects and takes up as suits its purpose; transforms each chemical the so-called incombustible, inorganic, or min- body it takes up, and fits it for the place it is eral ingredients which are necessary to the pro- intended to occupy in the building about to be duction of its perfect substance. erected; and with materials so collected and Of raw and simple materials like these, the prepared, it builds unceasingly-without wearyanimal can make nothing. Among them all, ing, and after a predetermined plan-green leaf, water is the only one it can with safety intro- graceful twig, towering stem, blooming flower, duce into its stomach, and upon this it cannot luscious fruit, nourishing seed; till through live or be sustained. It is upon the results of the wonderful working, mechanical and chemithe plant's labors-upon the substances of the cal, of that hidden speck of life which so long plant's body, the new and usually more complex slept in the microscopic germ, beauty and grace combinations which the living plant has manu- adorn the landscape, and inert useless matter factured from the simple compounds which has been abundantly converted into food for man. nature presents to it that the herbivorous How slow and limited is our most advanced animal can alone support itself. Out of these, chemical knowledge, compared with that easy by wonderful methods, which we cannot explain, skill so richly given to this tiny seedlet! the plant forms starch, sugar, fat, and gluten, in Let us now leave those substances which are all their varieties. So formed by the plant, naturally necessary to human life, and consider the animal eats them; digests and changes for a little those things which by habit have them anew by a further mysterious chemistry become to modern nations a kind of second nawhich we are only now beginning faintly to fol- ture. In looking to modern life in this point low; and finally fits them into appropriate of view, it appears widely distinguished not only places in its own body. This dead nature daily from that of classic times, but even from that of labors for the food of plants; the living plant the middle ages. Sugar, tea, coffee, cocoa, daily labors for the food of animals. In the brandy, and tobacco have all become familiar to order of nature, the plant must precede, and Christian Europe and America within the last accompany, and unceasingly work for the animal. 300 years. By the end of the 14th century, Alone, in the midst of physical nature, man the cultivation of sugar had already become imand all other animals would be helpless, forlorn, portant in Western Asia and Northern Africa. and short-lived. Brought into Spain by the Moors, and cultivatThus far, then, our science teaches us how ed in Andalusia, it was planted in the Madeiras different in relation to external things the life of by the Portuguese, who in 1520 possessed plants from the life of animais, and yet how already sixty sugar manufactories in the island

of St. Thomas alone. Thence it penetrated to We may pass briefly over cocoa, the ancient America with the Spaniards, and became a beverage and nutriment of the Mexican Incas, staple article of Spanish American growth. and still the favorite in modern times of Central Now, about 4500 millions of pounds of cane America, of Italy, and of Spain. It is consumsugar, produced chiefly in America, pass yearly ed to the extent of about 100 millions of pounds through the hands of European and American a year, and among 50 millions of men. merchants, while in addition nearly 500 millions But what is the chemistry of all this new of the same kind of sugar are extracted from food and drink, unknown to that ancient life, the beet-root in Northern Europe, and con- the manners and features of which form so sumed in the different countries of our more great a part of our study at school? What eastern continent. It was not till the year 1659 new craving in our common nature have they that sugar refining began to be practised in Eng-awakened, what old craving more agreeably land; and in 1700, the consumption of all satisfied? What is their physiological action, England was only 20 millions of pounds. Now, in short, and upon what chemical constituents we are not only the great refiners of Europe, does it depend? Why have entire nations so but by far the greatest consumers of sugar of readily fallen into the new habits, and why do every variety. In the year 1853, the consump- they so pertinaciously cling to them? tion of the United Kingdom amounted to 818 By her fireside, in her humble cottage, the millions of pounds of sugar, being at the rate lonely widow sits; the kettle simmers over the of 28 lbs. a year-upwards of half-a-pound ruddy embers, and the blackened teapot on the a week-for each of our population. What a hot brick prepares her evening drink. Her change in the habits and modes of living of the crust of bread is scanty; yet as she sips the people does this imply! warm beverage-little sweetened, it may be, The introduction and rapid spread of the with the produce of the sugar cane,-genial habit of using tea is still more recent and thoughts awaken in her mind; her cottage remarkable. The leaf was not brought to Eu- grows less dark and lonely, and comfort seems rope till about the beginning of the 17th century. to enliven the ill-furnished cabin. When our Sugar refineries were already in operation in suffering and wounded soldiers were brought England, when in 1664 the East India Company down frozen and bleeding from the trenches thought a couple of pounds of tea a not unroyal before Sebastopol to the port of Balaklava, the gift to present to the Queen of England. Now most welcome relief to their sufferings was a we consume at the rate of two pounds a head as pint of hot tea, which was happily provided for the yearly allowance of every individual in the them. Whence this great solace to the weary three kingdoms, and the total annual consump- and worn? Why out of scanty earnings does tion of the United Kingdom is about 25,000 the ill-fed and lone one cheerfully pay for the tons, or sixty millions of pounds! The use of seemingly unnourishing weekly ounce of tea? this leaf is specially great in China and Thibet, From what ever-open fountain does the daily in Russia, Holland, and England, and in the comfort flow which the teacup gently brings to states and provinces of North America. The the careworn and the weak?

entire quantity consumed over this wide area, The answer we are enabled to give to these among about 500 millions of men, is roughly questions is still very imperfect. Recent chemestimated at upwards of two thousand millions ical and chemico-physiological researches have of pounds. indeed thrown much interesting light on the Coffee, though less a favorite among us than nature, composition, and mode of action of the tea, is preferred to it by several of our Con- warm infusions we delight to drink, and we can tinental neighbors. On the whole, perhaps so far satisfactorily account for many of their the spread of coffee drinking during the last effects. We may expect our present views, 300 years has been more wonderful even than however, to be materially modified by the that of tea. It was not till the beginning of results of future research. the 15th century that it was introduced into In the first place, past experiment has shown Arabia from Abyssinia. About the middle of us that there is a remarkable chemical analogy the 16th, it began to be used in Constantinople, among the four substances Chinese tea, Paraand in spite of the opposition of priests and guay tea, coffee, and cocoa, which are chiefly Turkish doctors, it may now be considered as employed for the preparation of infused beverthe staple minor luxury of Mahomedan life. In ages. All of them in the roasted state in the middle of the 17th century (1652), the first which they are used, contain aromatic oils in coffee-house was open in London; and now, two minute proportion, to which the peculiar aroma hundred years after, the yearly consumption of of each is due. All contain also a proportion of coffee in the United Kingdom has reached the an astringent substance resembling the tannin large amount of 35 millions of pounds. The of gall-nuts or oak bark. In three of them, quantity of the coffee bean actually bought and Chinese tea, Paraguay tea, and coffee, is found sold is about 600 millions of pounds every year, a variable quantity of a peculiar white crystaland it is in daily use among perhaps 120 mil-line body, to which the name of theine or caffeine lions of men!

has been given; while in cocoa a different but sustain her strength as well with less common similar body exists, which is known by the food when she takes her tea along with it: name of theobromine. Of these three constitu- while she feels lighter at the same time in ents, which are all extracted by hot water, two spirits, more cheerful, and fitter for the dull -the volatile oil and the theine-are known work of life, because of this little indulgence." to exercise a peculiar action upon the system. The wide prevalence of the taste for infused The oil possesses narcotic properties, intoxicates, beverages, illustrates in a marked manner the occasions headaches and giddiness, and some- existence of common instinctive cravings among times paralysis in those who as tea-tasters are a large proportion of the human race. In tropmuch exposed to its influence. New tea con-ical as well as arctic regions, the practice of tains this oil in larger quantity than old tea using warm drinks equally prevails. Dr. Johndoes, and for this reason it is said that the son follows the topography of these harmless Chinese rarely use their tea till it has been kept stimulants in the following terms:over a year. The small proportion of it which "In Central America the Indian of native exists in tea as we get it in Europe, is not only blood and the Creole of mixed European race harmless, but is probably one source of the indulge alike in their ancient chocolate. In soothing exhileration which tea and coffee pro- South America the tea of Paraguay is an almost duce. universal beverage. The native North AmeriThe theine, again, is a bitter substance pos- can tribes have their Appalachian tea, their Ossessing tonic or strengthening qualities, but dis-wego tea, their Labrador tea, and many others. tinguished particularly by the property of re- From Florida to Georgia in the United States, tarding the natural waste of the animal body. and over all the West India islands, the naturMost people are now aware that the chief neces-alised European races sip their favorite coffee; sity for food to a full grown animal, arises from while over the Northern States of the Union, the gradual and constant wearing away of the and in the British Provinces, the tea of China is tissues and solid parts of its body. To repair in constant and daily use.

and restore the worn and wasted parts, food "In Europe we have no means of knowing must be constantly eaten and digested. And how long such tastes and practices have prethe faster the waste, the larger the quantity of vailed. The Romans, at their banquets, used food which must daily be consumed, to make up cups and saucers made of silver and richly emfor the loss which this waste occasions. Now bossed. They were nearly of the same shape as the introduction of a certain quantity of theine those now in use, and were employed for drinkinto the stomach lessens the amount of waste ing hot water out of. Whether it was custowhich in similar circumstances would otherwise mary to infuse herbs in this water on any occanaturally take place. It makes the ordinary sion we do not read. But in Holland and food consumed along with it, go further, there- England sage tea was in use till a very late pefore, or more correctly, lessens the quantity of riod: and its antiquity is shown by the statefood necessary to be eaten in a given time. A ment that the Dutch, in their carly intercourse similar effect in a somewhat less degree, is pro- with China, carried out dried sage leaves as an duced by the volatile oil, and therefore, the infu- article of traffic, and exchanged them against sion of tea, in which both these ingredients of those of the Chinese tea-tree. Now, however, the leaf are contained, affects the rapidity of every country in Europe has chosen for itself the natural waste in the tea-drinker in a very one or other of the familiar foreign beverages. marked manner. Spain and Italy delight in cocoa: France, GerAs age creeps on, the powers of digestion many, Sweden, and Turkey in coffee; Russia, diminish with the failing of the general vigor, Holland, and England in tea; while poor Iretill the stomach is no longer able to digest and land makes a warm drink for itself, out of the appropriate new food as fast as the body wears husks of the cocoa, the refuse of the chocolate away. When such is the case, to lessen the mills of Italy and Spain.

waste is to aid the digestive powers in maintain- "So all Asia feels the same want, and in difing the strength and bulk of the weakening ferent ways has long gratified it. Coffee, indiframe. "It is no longer wonderful therefore," genous in Abyssinia or the adjoining countries, says our author, "that tea and coffee should be has attached itself to the banner of the Arabian favorites on the one hand with the poor whose prophet, and has followed it wherever in Asia or supplies of substantial food are scanty. And on Africa his false faith has triumphed. Tea, a the other, with the aged and infirm, especially native of China, has spread spontaneously over of the feebler sex, whose powers of digestion the hill country of the Himalayas, the table and whose bodily substance have together begun land of Tartary and Thibet, and the plains of to fail. Nor is it surprising that the aged fe- Siberia, has climbed the Altais, overspread Rusmale whose earnings are barely sufficient to buy sia, and is equally despotic in Moscow as in what are called the common necessaries of life, St. Petersburg. In Sumatra the coffee-leaf should yet spare a portion of her small gains in yields the favorite tea of the dark-skinned popprocuring this grateful indulgence. She can ulation, while Central Africa boasts of the