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m trees, and shrubs, and flowers; the variety of of the increase. The result is, that out of the the seed vessels is incomputable. We have the many thousand different plants which cover the seeds (as in the pea tribe) regularly disposed in earth, not a single species, perhaps, has been lost parchment pods, which, though soft and mem- since the creation. branous, completely exclude the wet even in the When nature has perfected her seeds, her next heaviest rains; the pod also, not seldom (as in the care is to disperse them. The seed cannot anbean,) lined with a fine down; at other times (as swer its purpose, whilst it remains confined in the in the senna) distended like a blown bladder: or capsule. After the seeds therefore are ripened, we have the seed enveloped in wool, (as in the the pericarpium opens to let them out; and the cotton-plant,) lodged (as in pines) between the opening is not like an accidental bursting, but, for hard and compact scales of a cone, or barricadoed the most part, is according to a certain rule in (as in the artichoke and thistle) with spikes and each plant. What I have always thought very prickles; in mushrooms, placed under a penthouse; extraordinary; nuts and shells, which we can in fearns, within slits in the back part of the leaf; hardly crack with our teeth, divide and make way or (which is the most general organization of all) for the little tender sprout which proceeds from we find them covered by strong, close tunicles, the kernel. Handling the nut, I could barelly and attached to the stem according to an order conceive how the plantule was ever to get out of appropriated to each plant, as is seen in the several it. There are cases, it is said, in which the seed kinds of grains and of grasses.

vessel by an elastic jerk, at the moment of its exIn which enumeration, what we have first to plosjon, casts the seeds to a distance. We all notice is, unity of purpose under variety of expe. however know, that many seeds (those of most dients. Nothing can be more single than the composite flowers, as of the thistle, dandelion, &c.) design; more dirersified than the means. Pel- are endowed with what are not improperly called licles, shells, pulps, pods, husks, skin, scales wings; that is, downy appendages, by which they armed with thorns, are all employed in prosecut- are enabled to float in the air, and are carried oftening the same intention. Secondly; we may ob- times by the wind to great distances from the serve, that, in all these cases, the purpose is fulfilled plant which produces them. It is the swelling within a just and limited degree. We can per- also of this downy tuft within the seed-vessel, that ceive, that if the seeds of plants were more strongly seems to overcome the resistance of its coats, and guarded than they are, their greater security to open a passage for the seed to escape. would interfere with other uses. Many species

But the constitution of seeds is still more admi. of animals would suffer, and many perish, if they rable than either their preservation or their dispercould not obtain access to them. The plant would sion. In the body of ihe seed of every species of overrun the soil; or the seed be wasted for want plant, or nearly of every one, provision is made for of room to sow itself. It is, sometimes, as neces two grand purposes: first, for the safety of the germ; sary to destroy particular species of plants, as it is, secondly, for the temporary support of the future at other times, to encourage their growth. Here, plant. T'he sprout, as folded up in the seed, is as in many cases, a balance is to be maintained delicate and brittle beyond any other substance. between opposite uses. The provisions for the It cannot be touched without being broken. Yet preservation of seeds appear to be directed, chiefly in beans, peas, grass-seeds, grain, fruits, it is so against the inconstancy of the elements, or the fenced on all sides, so shut up and protected, that, sweeping destruction of inclement seasons. The whilst the seed itself is rudely handled, tossed into depredation of animals, and the injuries of acci- sacks, shovelled into heaps, the sacred particle, dental violence, are allowed for in the abundance the miniature plant, remains unhurt. It is wonder

ful also, how long many kinds of seeds, by the help the pulp of an orange, the meat of a plum, the fatness of their integuments, and perhaps of their oils, of the olive, appear to be more than sutricient for the stand out against decay. A grain of mustard-seed nourishing of the seed or kernel. The event shows, has been known to lie in the earth for a hundred that this redundancy, if it he one, ministers to the sup. years; and, as soon as it had acquired a favouraport and gratification of animal natures; and when we observe a provision to be inore than sufficient for one

ble situation, to shoot as vigorously as if just gapurpose, yet wanted for another purpose, it is not unfair thered from the plant. Then, as to the second to conclude that both purposes were contemplated to point, the temporary support of the future plant, gether. It favours this view of the subject to remark, the matter stands thus. In grain, and pulse, and that fruits are not (which they might have been) ready kernels, and pippins, the germ composes a very all together, but thai they ripen in succession throughout a great part of the year; some in summer ; some in small part of the seed. The rest consists of a nuautumn; that some require the slow maturation of the tritious substance, from which the sprout draws winter, and supply the spring; also that the coldest its aliment for some considerable time after it is ples, melons, are the natural produce of warın climates, put forth; viz. until the fibres, shot out from the and contribute greatly, by their coolness, to the refresh other end of the seed, are able to imbibe juices ment of the inhabitants of those countries.

from the earth, in a sufficient quantity for its deI will add to this note the following observation mand. It is owing to this constitution, that we communicated to me by Mr. Brinkley : "The eatable part of the cherry or peach first serves

see seeds sprout, and the sprouts make a considerthe purposes of perfecting the seed or kernel, by means able progress, without any earth at all. It is an of vessels passing through the stone, and which are economy also, in which we remark a close analofected, the stone becomes hard, and the vessels cease animals. The same point is provided for, in the very visible in a p-ach-stone. After the kernel is per- gy between the seeds of plants, and the eggs of their functions. But the substance surrounding the stone is not then thrown away as useless. That which same manner in both. In the egg, the residence nel, now receives and retains to itself the whole of the minute part of the contents. The white and the was before only an instrument for perfecting the ker of the living principle, the cicatrix forms a very sun's influence, and thereby becomes a grateful

food to white only is expended in the formation of the protecting the kernel! The intervention of the stone chicken. The yolk, very little altered or diminishprevents ibe second use from interfering with the first." | ed, is wrapped up in the abdomen of the young

bird, when it quits the shell; and serves for its , issue, close to each other, two shoots: one bearing nourishment, till it have learnt to pick its own the flower and fruit; the other, drawn out into a food. This perfectly resembles the first nutrition wire, a long, tapering, spiral tendril, that twists of a plant. In the plant, as well as in the animal, itself round any thing which lies within its reach, the structure has every character of contrivance Considering, that in this class two purposes are to belonging to it: in both it breaks the transition be provided for, (and together,) fructification and from prepared to unprepared aliment; in both, it support, the fruitage of the plant, and the susten. is prospective and compensatory: În animals tation of the stalk, what means could be used more which suck, this intermediate nourishment is sup- effectual, or, as I have said, more mechanical, than plied by a different source.

what the structure presents to our eyes? Why, In all subjects, the most common observations or how, without a view to this double purpose;

do are the best, when it is their truth and strength two shoots, of such different and appropriate which have made them common. There are, of forms, spring from the same joint, from contiguthis sort, two concerning plants, which it falls ous points of the same stalk ? It never happens within our plan to notice. The first relates to, thus in robust plants, or in trees. “We see not what has already been touched upon, their germi- (says Ray) so much as one tree, or shrub, or herb, nation. When a grain of corn is cast into the that hath a firm and strong stem, and that is able ground, this is the change which takes place. to mount up and stand alone without assistance, From one end of the grain issues a green sprout; furnished with these tendrils.” Make only so from the other a number of white fibrous threads. simple a comparison as that between a pea and a How can this be explained? Why not sprouts bean. Why does the pea put forth tendrils, the from both ends? why not fibrous threads from bean not; but because the stalk of the pea cannot both ends? To what is the difference to be refer- support itself, the stalk of the bean can? We red, but to design; to the different uses which the may add, also, as a circumstance not to be overparts are thereafter to serve; uses which discover looked, that in the pea tribe, these clasps do not themselves in the sequel of the process? The make their appearance till they are wanted; till sprout, or plumule, struggles into the air; and be the plant has grown to a height to stand in need comes the plant, of which, from the first

, it con- of support. tained the rudiments: the fibres shoot into the This word " support' suggests to us a reflection earth; and, thereby, both fix the plant to the upon a property of grasses, of corn, and canes ground, and collect nourishment from the soil for The hollow stems of these classes of plants are its support. Now, what is not a little remarkable, set, at certain intervals, with joints. These joints the parts issuing from the seed take their respect are not found in the trunks of trees, or in the jve directions, into whatever position the seed solid stalks of plants. There may be other uses itself happens to be cast. If the seed be thrown of these joints; but the fact is, and it appears to into the wrongest possible position; that is, if the be, at least, one purpose designed by them, that ends point in the ground, the reverse of what they they corroborate the stem; which, by its length ought to do, every thing, nevertheless, goes on and hollowness, would otherwise be too liable to right. The sprout, after being pushed down a break or bend. little way, makes a bend, and turns upwards; the Grasses are Nature's care. With these she fibres, on the contrary, after shooting at first up-clothes the earth; with these she sustains its inwards, turn down. Of this extraordinary vegeta- habitants. Cattle feed upon their leaves; birds ble fact, an account has lately been attempted to upon their smaller seeds; men upon the larger: be given. "The plumule (it is said) is stimulated for, few readers need be told that the plants, which by the air into action, and elongates itself when produce our bread-corn, belong to this class. In it is thus most excited; the radicle is stimulated those tribes, which are more generally considered by moisture, and elongates itself when it is thus as grasses, their extraordinary means and powers most excited. Whence one of these grows up- of preservation and increase, their hardiness, their ward in quest of its adapted object, and the other almost unconquerable disposition to spread, their downward."* Were this account better verified faculties of reviviscence, coincide with the intenby experiment than it is

, it only shifts the con- tion of nature concerning them. They thrive trivance. It does not disprove the contrivance; under a treatment by which other plants are deit only removes it a little farther back. Who, to stroyed. The more their leaves are consumed, use our author's own language, "adapted the ob- the more their roots increase. The more they are jects ?” Who gave such a quality to these connate trampled upon, the thicker they grow. Many of parts, as to be susceptible of different "stimula- the seemingly dry and dead leaves of grasses retion;" as to be "excited” each only by its own ele vive, and renew their verdure in the spring. In ment, and precisely by that which the success of lofty mountains, where the summer heats are not the vegetation requires ? I say, " which the suc- sufficient to ripen the seeds, grasses abound, which cess of the vegetation requires;" for the toil of the are viviparous, and consequently able to propagate husbandman would have been in vain; his labo- themselves without seed. It is an observation, rious and expensive preparation of the ground in likewise, which has often been made, that herbivain ; if the event must, after all, depend upon the vorous animals attach themselves to the leaves of position in which the scattered seed was sown. grasses; and, if at liberty in their pastures to Not one seed out of a hundred would fall in a range and choose, leave untouched the straws right direction.

which support the flowers.* Our second observation is upon a general pro The GENERAL properties of vegetable nature, or perty of climbing plants, which is strictly me- properties common to large portions of that kingchanical

. In these plants, from each knot or dom, are almost all which the compass of our arjoint, or, as botanists call it, axilla, of the plant, gument allows to bring forward. It is impossible

• Darwin's Phytologia, p. 144.

* Withering, Bot. Arr. vol. i p. 28 ed. 2d.

to follow plants into their several species. We structure of this plant, we find that instead of its may be allowed, however, to single out three or being neglected, Nature has gone out of her course four of these species as worthy of a particular no to provide for its security, and to make up to it for tice, either by some singular mechanism, or by all its defects. The seed-vessel, which in other some peculiar provision, or by both.

plants is situated within the cup of the flower, or 1. În Dr. Darwin's' Botanic Garden (1. 395, just beneath it, in this plant lies buried ten or note,) is the following account of the vallisneria, twelve inches under ground within the bulbour as it has been observed in the river Rhone. — root. The tube of the flower, which is seldom “They have roots at the bottom of the Rhone. more than a few tenths of an inch long, in this The flowers of the female plant float on the sur plant extends down to the root. The stiles in all face of the water, and are furnished with an elas- cases reach the seed-vessel; but it is in this, by an tic, spiral stalk, which extends or contracts as the elongation unknown to any other plant. All these water rises or falls; this rise or fall, from the tor- contribute to one end. “ As this plant blossoms rents which flow into the river, often amounting late in the year, and probably, would not have to many feet in a few hours. The flowers of the time to ripen its seeds before the access of winter, male plant are produced under water; and, as which would destroy them: Providence has consoon as the fecundating farina is mature, they se- trived its structure such, that this important office parate themselves from the plant; rise to the sur-may be performed at a depth in the earth out of face; and are wafted by the air, or borne by the reach of the usual effects of frost."' * That is to currents, to the female flowers.” Our attention say, in the autumn nothing is done above ground in this narrative will be directed to two particu- but the business of impregnation ; which is an aflars: first, to the mechanism, the "elastic, spiral fair between the anthere and stigmata, and is prostalk,” which lengthens or contracts itself accord- bably soon over. The maturation of the impreg. ing as the water rises or falls; secondly, to the nated seed, which in other plants proceeds within provision which is made for bringing the male a capsule, exposed together with the rest of the Hower, which is produced under water, to the fe- Aower to the open air, is here carried on, and dur. male flower which floats upon the surface. ing the whole winter, within the heart, as we may

II. My second example I take from Wither- say, of the earth, that is, “out of the reach of the ing's Arrangement, vol. ii. p. 209. ed. 3. “The usual effects of frost." But then a new difficulty cuscuta europæa is a parasitical plant. The seed presents itself: seeds, though perfected, are known opens, and puts forth a little spiral body, which not to vegetate at this depth in the earth. Our does not seek the earth, to take root; but climbs seeds, therefore, though so safely lodged, would, in a spiral direction, from right to left, up other after all, be lost to the purpose for which all seeds plants, from which, by means of vessels, it draws are intended. Lest this should be the case, "a its nourishment.” The “little spiral body” pro- second adnyirable provision is made to raise them ceeding from the seed, is to be compared with the above the surface when they are perfected, and to fibres which seeds send out in ordinary cases : sow them at a proper distance; viz. the germ and the comparison ought to regard both the form grows up in the spring, upon a fruit stalk, acof the threads and the direction. They are companied with leaves. The seeds now, in comstraight; this is spiral. They shoot downwards; mon with those of other plants, have the benefit this points upwards. In the rule, and in the ex- of the summer, and are sown upon the surface. ception, we equally perceive design.

The order of vegetation externally is this :- The III. A better known parasitical plant is the ever-plant produces its flowers in September; its leaves green shrub, called the mistletoe. What we have and fruits in the spring following. to remark in it, is a singular instance of compen V. I give the account of the d:onæa muscipula, sation. No art hath yet made these plants take an extraordinary American plant, as some late root in the earth. Here therefore might seem to be authors have related it: but whether we be yet a mortal defect in their constitution. Let us ex- enough acquainted with the plant, to bring every amine how this defect is made up to them. The part of this account to the test of repeated and seeds are endued with an adhesive quality, so familiar observation, I am unable to say. “Its tenacious, that if they be rubbed upon the smooth leaves are jointed and furnished with two rows of bark of almost any tree, they will stick to it. And strong prickles; their surfaces covered with a then what follows?. Roots, springing from these number of minute glands, which secrete a sweet Beeds, insinuate their fibres into the woody sub- liquor that allures the approach of flies. When stance of the tree; and the event is, that å mis- these parts are touched by the legs of flies, the tletoe plant is produced nexi winter.* 'Of no other two lobes of the leaf instantly spring up, the rows plant do the roots refuse to shoot in the ground; of prickles lock themselves fast together, and of no other plant do the seeds possess this adhe- squeeze the unwary animal to death." | Here, sive, generative quality, when applied to the bark under a new model, we recognise the ancient plan of trees.

of nature, viz. the relation of parts and provisions IV. Another instance of the compensatory sys- to one another, to a common office, and to the tem is in the autumnal crocus, or meadow saffron utility of the organized body to which they belong. (colchicum autumnale.) I have pitied this poor The attracting syrup, the rows of strong prickles, plant a thousand times. Its blossom rises out of their position so as to interlock the joints of the the ground in the most forlorn condition possi- leaves ; and, what is more than the rest, that sinble; without a sheath, a fence, a calyx, or even gular irritability of their surfaces, by which they a leaf to protect it: and that, not in the spring, close at a touch ; all bear a contributory part in not to be visited by summer suns, but under all producing an effect, connected either with the the disadvantages of the declining year. When defence or with the nutrition of the plant. we come, however, to look more closely into ths

. Withering, ubi supra, p. 360. * Withering, Bot. Arr. vol. i. p. 203. ed. 21.

Smellie's Phil. of Nat. Hist. vol. i. p. 5.

CHAPTER XXI.

phere raises the water and leaves the salt. Pure

and fresh as drops of rain descend, they are colThe Clements.

lected from brine. If evaporation be solution

(which seems to be probable,) then the air disWAEN we come to the elements, we take leave solves the water, and not the salt. Upon whatof our mechanics; because we come to those ever it be founded, the distinction is critical; so things, of the organization of which, if they be much so, that when we attempt to imitate the organized, we are confessedly ignorant. This ig- process by art, we must regulate our distillation norance is implied by their name. To say the with great care and nicety, or, together with the truth, our investigations are stopped long before water, we get the bitterness, or at least, the distastewe arrive at this point. But then it is for our fulness, of the marine substance: and after all it comfort to find, that a knowledge of the constitu- is owing to this original elective power in the air, tion of the elements is not necessary for us. For that we can effect the separation which we wish, instance, as Addison has well observed, “ we know by any art or means whatever. water sufficiently, when we know how to boil, By evaporation, water is carried up into the how to freeze, how to evaporate, how to make it air; by the converse of evaporation, it falls down fresh, how to make it run or spout out, in what upon the earth. And how does it fall ? Not by quantity and direction we please, without know- the clouds being all at once reconverted into ing what water is.” The observation of this ex- water, and descending like a sheet; not in rushing cellent writer has more propriety in it now, than it down in columns from a spout; but in moderate had at the time it was made: for the constitution, drops, as from a colander. Our watering-pots are and the constituent parts, of water, appear in made to imitate showers of rain. Yet, a priori, I some measure to have been lately discovered; yet should have thought either of the two former it does not, I think, appear, that we can make any methods more likely to have taken place than the better or greater use of water since the discovery, last. than we did before it.

By respiration, flame, putrefaction, air is renderWe can never think of the elements, without ed unfit for the support of animal life. By the reflecting upon the number of distinct uses which constant operation of these corrupting principles, are consolidated in the same substance. The air the whole atmosphere, if there were no restoring supplies the lungs, supports fire, conveys sound, causes, would come at length to be deprived of its reflects light diffuses smells, gives rain, wafts ships, necessary degree of purity. Some of these causes bears up birds. 'EE 088505 ** **T*! water, be- seem to have been discovered; and their efficacy sides maintaining its own inhabitants, is the uni- ascertained by experiment. And so far as the versal nourisher of plants, and through them of discovery has proceeded, it opens to us a beautiful terrestrial animals; is the basis of their juices and and a wonderful economy. Vegetation proves to fluids ; dilutes their food; quenches their thirst, be one of them. A sprig of mint, corked up with floats their burdens. Fire warms, dissolves, en a small portion of foul air, placed in the light, lightens; is the great promoter of vegetation and renders it again capable of supporting life or flame. life, if not necessary to the support of both. Here, therefore, is a constant circulation of bene

We might enlarge, to almost any length we fits maintained between the two great provinces pleased, upon each of these uses; but it appears of organized nature. The plant purifies, what to me almost sufficient to state them. The few the animal has poisoned; in return, the contamiremarks which I judge it necessary to add, are as nated air is more than ordinarily nutritious to the follow:

plant. Agitation with water turns out to be I. Air is essentially different from earth. another of these restoratives. The foulest air, There appears to be no necessity for an atmos- shaken in a bottle with water for a sufficient phere's investing our globe; yet it does invest it : length of time, recovers a great degree of its purity. and we see how many, how various, and how im- Here then again, allowing for the scale upon portant, are the purposes which it answers to which nature works, we see the salutary effects of every order of animated, not to say of organized storms and tempests. The yesty waves, which beings, which are placed upon the terrestrial sur- confound the heaven and the sea, are doing the face. I think that every one of these uses will be very thing which was done in the bottle. Nounderstood upon the first mention of them, except thing can be of greater importance to the living it be that of reflecting light, which may be ex- creation, than the salubrity of their atmosphere. plained thus :- If I had the power of seeing only it ought to reconcile us therefore to these agitaby means of rays coming directly from the sun, tions of the elements, of which we sometimes whenever I turned my back upon the luminary, Í deplore the consequences, to know that they tend, should find myself in darkness. If I had the powerfully to restore to the air that purity, which power of seeing by reflected light, yet by means so many causes are constantly impairing only of light reflected from solid masses, these II. In water, what ought not a little to be admasses would shine indeed, and glisten, but it mired, are those negative qualities which constiwould be in the dark. The hemisphere, the sky, tute its purity. Had it been vinous, or oleaginous, the world, could only be illuminated, as it is illu- or acid; had the sea been filled, or the rivers minated, by the light of the sun being from all flowed, with wine or milk; fish, constituted as sides, and in every direction, reflected to the eye, they are, must have died; plants, constituted as by particles, as numerous, as thickly scattered, they are, would have withered; the lives of animals and as widely diffused, as are those of the air. which feed upon plants, must have perished. Its

Another general quality of the atmosphere is very insipidity, which is one of those negative quathe power of evaporating fluids. The adjust- lities, renders it the best of all menstrua. Having ment of this quality to our use is seen in its action no taste of its own, it becomes the sincere vehicle upon the sea. In the sea, water and salt are of every other. Had there been a taste in water, mixed together most intimately, yet the atmos- be it what it might, it would have infected every

thing we ate or drank, with an importunate repe-| ficult to conceive, it is easy to prove. A drop of tition of the same flavour.

tallow, expended in the wick of a farthing candle, Another thing in this element, not less to be shall send forth rays sufficient to fill a hemisphere admired, is the constant round which it travels; of a mile diameter; and to fill it so full of these and by which, without suffering either adultera-rays, that an aperture not larger than the pupil of tion or waste, it is continually offering itself to the an eye, wherever it be placed within the hemiwants of the habitable globe. From the sea are sphere, shall be sure to receive some of them. exhaled those vapours which form the clouds: What floods of light are continually poured from these clouds descend in showers, which, pene- the sun, we cannot estimate; but the immensity trating into the crevices of the hills, supply of the sphere which is filled with particles even if springs: which springs flow in little streams into it reached no farther than the orbit of the earth, the valleys; and there uniting, become rivers; we can in some sort compute: and we have reason which rivers, in return, feed the ocean. So there to believe, that, throughout this whole region, the is an incessant circulation of the same fuid; and particles of light lie, in latitude at least, near to not one drop, probably, more or less now than one another. The spissitude of the sun's rays at there was at the creation. A particle of water the earth is such, that the number which falls takes its departure from the surface of the sea, in upon a burning-glass of an inch diameter, is suforder to fulfil certain important offices to the earth; ficient, when concentrated, to set wood on fire. and, having executed the service which was as The tenuity and the velocity of particles of signed to it, returns to the bosom which it left. light, as ascertained by separate observations, may

Some have thought, that we have too much be said to be proportioned to each other; both water upon the globe, the sea occupying above surpassing our utmost stretch of comprehension; three quarters of its whole surface. But the but proportioned. And it is this proportion alone expanse of ocean, immense as it is, may be no which converts a tremendous element into a wel more than sufficient to fertilize the earth. Or, come visitor. independently of this reason, I know not why the It has been observed to me by a learned friend, sea may not have as good a right to its place as the as having often struck bis mind, that if light had land. It may proportionably support as many in- been made by a common artist, it would have been habitants; minister to as large an aggregate of en- of one uniform colour; whereas, by its present joyment. The land only affords a habitable sur composition, we have that variety of colours, face; the sea is habitable to a great depth. which is of such infinite use to us for the distin

III. Of fire, we have said that it dissolves. The guishing of objects; which adds so much to the only idea probably which this term raised in the beauty of the earth, and augments the stock of reader's mind, was that of fire melting metals, our innocent pleasures. resins, and some other substances, fluxing ores, With which may be joined another reflection, running glass, and assisting us in many of our viz. that, considering light as compounded of operations, chymical or culinary. Now these rays of seven different colours, (of which there are only uses of an occasional kind, and give can be no doubt, because it can be resolved into us a very imperfect notion of what fire does for us. these rays by simply passing it through a prism,) The grand importance of this dissolving power, the constituent parts must be well mixed and the great office indeed of fire in the economy of blended together, to produce a fluid so clear and nature, is keeping things in a state of solution, colourless, as a beam of light is, when received that is to say, in a state of fluidity. Were it not from the sun. for the presence of heat, or of a certain degree of it, all fluids would be frozen. The ocean itself would be a quarry of ice; universal nature stiff and dead.

CHAPTER XXII. We see, therefore, that the elements bear not only a strict relation to the constitution of orga

Astronomy.* nized bodies, but a relation to each other. Water could not perform its office to the earth without My opinion of Astronomy has always been, air; nor exist, as water, without fire.

that it is not the best medium through which to IV. Of light (whether we regard it as of the prove the agency of an intelligent Creator; but same substance with fire, or as a different sub- that, this being proved, it shows, beyond all other stance,) it is altogether superfiuous to expatiate sciences, the magnificence of his operations. The upon the use. No man disputes it. The observa- mind which is once convinced, it raises to subtions, therefore, which I shall offer, respect that limer views of the Deity than any other subject little which we seem to know of its constitution. affords; but it is not so well adapted, as some

Light travels from the sun at the rate of twelve other subjects are, to the purpose of argument. millions of miles in a minute. Urged by such a We are destitute of the means of examining the velocity, with what force must its particles drive constitution of the heavenly bodies. The very against (I will not say the eye, the tenderest of simplicity of their appearance is against them. animal substances, but) every substance, animate We see nothing, but bright points, luminous cir. or inanimate, which stands in its way! It might cles, or the phases of spheres reflecting the light seem to be a force sufficient to shatter to atoms which falls upon them. Now we deduce design the hardest bodies.

from relation, aptitude, and correspondence of How then is this effect, the consequence of such parts. Some degree, therefore, of complerity is prodigious velocity, guarded against ? By a proportionable minuteness of the particles of which * For the articles in this chapter marked with an as. light is composed. It is impossible for the human terisk, I am indebted to some obliging communications

received (through the hands of the Lord Bishop of El. mind to imagine to itself any thing so small as a par- phin) from the Rev J. Brinkley, M. A. Andrew's Pro. ticle of light. But this extreme exility, though dif-| fessor of Astronomy in the University of Dublin

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