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quisite workmanship, which were executed | mosphere, and the condensation of steam. at that time, entirely by his hands. On his exertions for its improvement, it

The shop of Watt became, too, a sort would be interesting to enlarge; but a of academy, where all the learned in Glas- brief notice is all that is now practicable. gow resorted to discuss points of literature | The chief result was the condensation of and science. Whenever any puzzle came the steam in a vessel detached from the in their way, they went to this young cylinder in which the piston works, by mechanician, knowing that every thing which incalculable advantages were seto which his attention was directed, was cured. After overcoming much opposithe beginning of a new and serious study, tion from interest and prejudice, he conand that he would not quit it until he structed an engine, and used it with comhad turned it to some account. On one plete success at Carron, with the founder occasion the solution of a problem seemed of which, Dr. Roebuck, he entered into to require the perusal of a work of Leu- partnership. On some reverse, leading pold's, and he forthwith learned German. to temporary embarrassment, Watt gave At another time, and for a similar reason, up his invention, for which he had taken he made himself master of Italian. Yet out a patent, changed his course, and was with an extraordinary acquaintance with employed for the next eight years, in mathematical and mechanical philosophy, trigonometrical surveys and operations in and an aptitude and disposition for mak- Scotland. In 1774, he became connected ing constant attainments, there was no- with Mr. Boulton of Soho, near Birmingthing of that pride and ostentation which ham, which led to the two friends petiso greatly detract from the influence of tioning parliament for an extension of some men, but a simplicity, candour, and the patent for the steam engine, it having generosity of spirit, which awakened the now only a few years to run, and after strong and cordial attachment of his nu- violent opposition, they gained their obmerous acquaintances. It is worthy of ject. Steam engines now came into use remark, that his various studies were in all the mining districts, and Boulton pursued in the night, and never inter- and Watt received, as their remuneration, fered with the proper labours of the day. the third part of the fuel which was saved He seemed to find pleasure not only in by each of their machines. almost unceasing labours, but in the most It appears, however, that the Cornish difficult undertakings, and those for which miners discovered increased reluctance he might have been considered the least from year to year in paying the rent due adapted. As a proof of this, it may be for their engines, and availed themselves stated, that though he was utterly insens- of the first difficulties occasioned by pirates ible to the charms of music, and never of the invention, to pretend that they learned to distinguish a single note from were free from all obligations. A long another, he undertook to build an organ. and costly litigation was the consequence; Even here he was also successful. “The but in the end, Boulton and Watt were new instrument,” says his biographer, successful. Happily, the annoyance and "displayed the most important improve- irritation experienced by the latter, did ments in its mechanical parts, in the not impede his efforts for the improvement stops, in the indications and regulations of his engines, and the enlargement of of the strength of the blast; but you will their power. The pumps, which were at be astonished to learn, that its harmonic first merely instruments of exhaustion, he qualities were not less remarkable, and changed into agents of great power and delighted the best performers. Watt utility. Regularity of action was also solved an important part of the problem ; attained, so that the steam engine is he found out the temperament assigned equally successful in embroidering musby a master of the art, by help of the lins, or forging anchors; in weaving the phenomena of the beats of imperfect con- most delicate fabrics, or giving rapid sonances, then very ill understood, and of motion to ponderous machinery. A fur'which he could have gained no know ther discovery was that of the expansion of ledge, except from the profound but very steam; so that in the steam engines of Cornobscure work of Dr. Robert Smith of wall, one bushel of coal did the work of Cambridge.'

twenty men, for nearly ten hours, and at the At the period in which those labours cost in those districts of only nine-pence. were pursued, the steam engine was a Sir John Herschel has strikingly illusrude machine, the result of simple ex- trated the importance of this invention periments on the compression of the at- by the following comparisons :

“ The ascent of Mont Blanc, from the Watt; who directing the force of an orivalley of Chamouni, is considered, and ginal genius, early exercised in philosojustly so, as the most toilsome undertak-phical research, to the improvement of ing that a man can perform in two days. the steam engine, enlarged the resources Thus the maximum of mechanical exer- of his country, increased the power of tion, which we are capable of making in man, and rose to an eminent place among twice twenty-four hours, is measured by the most illustrious followers of science, the raising the weight of our body to the and the real benefactors of the world." height of Mont Blanc. This exertion, or No less than five statues have been its equivalent, a steam engine will make erected to Watt's memory. The benefits by consuming two pounds of coal! Watt conferred on mankind by his labours, has then made it appear, that the strength have been described by many eminent which a man working for a day can exert, men, in terms of the highest panegyric. is no more than is contained in a pound It may, however, be well to observe, parof coal. Herodotus relates, that the con- ticularly for the sake of the youthful struction of the great pyramid of Egypt reader, that the sketch of his course now occupied a hundred thousand men for given, is one that may serve to refute a twenty years. The pyramid is built of popular error. The natural endowments calcareous stone; its cubic contents can of some men are obviously superior to be easily calculated; and hence the con- those of the multitude; but it ought not clusion is drawn, that its weight is about to be assumed, as it often is, that to these thirteen millions of millions of pounds. alone great success in life is to be traced, To raise this weight to the height of a On the contrary, it is to the diligent and hundred and twenty-five feet, the height unwearied culture and improvement of of the centre of gravity of the pyramid, the powers God has bestowed, that distinit would be necessary to burn, under the guished persons are mainly indebted for boiler of a steam engine, six hundred and their celebrity and usefulness. The harvest thirty chaldrons of coal. There is a is reaped in these instances, as in others, foundry which consumes a greater quan

not as the result of spontaneous and extity of fuel than this every week!” uberant growth, but as the reward of

The health of Watt seemed to strengthen solicitude and toil. Watt was no less with his advancing years, while his mental remarkable for his indefatigable labours, powers retained all their former vigour. than for the early activity and versatility Once he thought they were beginning to of his powers. It may indeed be quesfail: he then sought for some mode of tioned whether the latter were not far study to try them by; and testing himself surpassed by the former. When sir Isaac by the Anglo-Saxon language, which is Newton was asked how he discovered one of some difficulty, he found in the gravitation, he answered, “ By always facility with which he mastered it, there thinking about it,” and, says M. Arago, was little ground for apprehension. He “in these few simple words of the imafterwards constructed a machine de- mortal author of the Principia, we may signed to copy with despatch and mathe- lay open to the eyes of all, the true secret matical exactness, pieces of statuary and of men of genius.” Let no one, then, sculpture of all dimensions. As he made suppose that either the inferiority or the presents of its performances, he used to superiority of his powers, exempts him describe them as “ the first attempts of a from diligent and continued effort. It is young artist entering on his eighty-third with all, a matter of solemn obligation year.' He died on the 25th of August, to improve to the utmost every gift of 1819.

the all-wise and gracious Creator. A colossal statue of Watt, by Chantrey, It ought, at the same time, to be from which the engraving at the head clearly perceived, that the welfare of the of this article was taken, is in Westminster soul should receive the first and chief Abbey. The inscription, recording simply regard. Compared with eternal salvation, his birth and his death, is as follows: all the honours of this life are lost in

“Not to perpetuate a name which must abject insignificance. The Christian is endure while the peaceful arts flourish, the highest style of man; and eminence but to show that mankind have learnt to in piety is to be traced to the Divine honour those who best deserve their gra- blessing on “patient continuance in well titude, the King, his Ministers, and many doing. of the Nobles and Commoners of the At the commencement of a new year, realm, raised this monument to Jaines then, let us all be concerned to enter on a

new career.

due,"

There is not one of us who | emanates from Him of whom it is writmay not do more than he has hitherto ten, “ Thou bidest thy face, they are accomplished, and that with a simpler troubled : thou takest away their breath, reliance on Him who is Almighty. Let they die, and return to their dust. Thou each one, therefore, begin with himself, sendest forth thy spirit, they are created : and then he may listen to the words of and thou renewest the face of the earth,” the poet, as he recurs to the past : Psa. civ. 29, 30, " Wake thou that sleepest in enchanted bowers,

It is our present design to carry out Lest these lost years should haunt thee on the

the subject, to which, brief allusion has night

been already made. (See Visitor 1840, When death is waiting for thy numbered hours, To take their swift and everlasting flight;

page 429.) We may begin by observing Wake, ere the earth-born charm unnerve thee that naturalists have given the term acrita

quite, And be thy thoughts to work divine address'd;

(a a, negative, kpivw, crino, to perceive) to Do something, do it soon, with all thy might; a group or assemblage of animals, the lowAn angel's wing would droop, if long at rest, est in the scale, because in their composiAnd God himself, inactive, were no longer bless'd.

tion (regarding the assemblage in a general Some high or humble enterprize of good light) no distinct nerves are to be perceived. Contemplate, till it shall possess thy mind, To this group belong the sponges and Become thy study, pastime, rest, and food, And kindle in thy heart a flame refined.

zoophytes. The acrita are, with a few Pray Heaven for firmness, thy whole soul to bind exceptions, tenants of the water. Their With thoughts all fixed, and feelings purely kind; forms are very varied; but they consist Strength to complete, and with delight review, essentially of a gelatinous substance, of And grace to give the praise where all is ever which the solid constituents bear but a

W.

trifling proportion to the fluid. This gelatine is sometimes unsupported by

any kind of framework, but generally it SPONGES AND ZOOPHYTES.-No. I.

either invests, or is contained in a horny Sponges and Zoophytes are considered or a calcareous support, which is elaboas beings lowest in the scale of animal rated from it, and which varies greatly organization; but they are by no means

in outward form and appearances. among the least wonderful of the works Though no nervous fibres have been of the Creator. Indeed, in some respects, detected, still it is most probable that they excite more than common interest, nervous matter, in the form of a subtle as discovering to the reflective mind the fluid, or of atoms beyond our detection, utmost simplicity of organization, con- may be blended with the gelatine. True joined with animal, not vegetable life. blood vessels do not exist; yet in some Their organization is, in fact, surpassed groups canals are excavated in the subin intricacy by that of many vegetables, stance of the gelatine, through which perhaps by most; yet, simple as it is, it absorbed fluids circulate and are carried is only the first of a series of gradations, to a central cavity. This apparatus fulwhich leads us through a succession of fils at once the double office of aerating forms, up to the highest orders, namely, the system, (for oxygen is the sine qua fishes, reptiles, birds, and mammalia. non of animal life,) and of supplying it

It has often been said, that nature does with nutrition; which it cannot be doubtnothing per saltum; in other words, that ed is absorbed and assimilated. In some the Almighty has been pleased to show of the acrita, indeed, a more perfect alihis power in the establishment of a plan mentary and aerating set of organs is of creation, founded upon an increase in present, and their use cannot be misthe gradual developement of organization. taken. Thus, as we ascend the scale of animated The powers of locomotion enjoyed by nature, we trace the first appearance, the the acrita differ exceedingly; and many, expansion and the perfection of organs ; fixed plant-like, live and die on one spot. we discover what are the essential con- None have true limbs, but many have ditions of life, and what are the acces tentacles, or feelers, by means of which sories ; with what simplicity of structure they secure their prey.

There is no vitality may be associated, and with what distinction of sexes; and reproduction complexity and perfection of structure it takes place either by simple division, or is conjoined. We learn, moreover, that by buds termed gemmules, which sprout, structure itself, whether simple or com- and become detached from the parent, plex, is the result of the power of God and ultimately assume their true and perin creation, and that the vital principle manent form. In numerous instances,

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the acrita present the singular condition servations respecting the mode in which of compound animals. Groups of living the nutrition and reproduction of the beings vitally united together, consti- sponge is effected. We may add, howtute one animal, if we regard it in some ever, that as every part of a sponge is points of structure; but many, if we re- similarly organized, and, that as every gard it in others The acrita then forms part carries on the same functions, it will the lowest great section of the animal not surprise us to learn that if divided kingdom: and of this section, the sponges into pieces, every portion becomes an are the lowest.

independent and distinct being, growing The sponges (Porifera) have been re- and assuming the characteristics of the garded by naturalists at no distant date, species. and are so by some at present, as belong- We have designated the fibrous strucing to the vegetable kingdom ; nor can ture of the sponge, as the framework or we be surprised at it. Who that takes rude skeleton of the living animal; and up a piece of common sponge, as sold in it is to be observed, that the characters commerce, but would consider it as a sort presented by this framework, differ greatly of vegetable, even if told that when first in the various species, which indeed are procured it was covered with a gelatinous extremely numerous. film; he would, or might reply, with In the common sponge the fibres are some degree of force, So are many species elastic and horny in their texture, and of sea-weed, (alge et fuci,) and he might when highly magnified appear to be add, Where is its sensibility, and its tubular. In other species, the framework motion? it does not betray even the irri-consists of a firm, inflexible tissue of intertability of the sensitive plant, the sun- crossing filaments, also tubular, and the flower, or the daisy that folds at eventide. living gelatine exhibits bands of a more It is fixed, rooted to one spot, it has no cartilaginous consistency than ordinary, definite alimentary canal, and it cannot and is also more or less replete with even select its food. True! so close, minute crystallized spicula. The spicula indeed, does the animal kingdom trench are usually simple needle-like points, but upon the vegetable; so nearly at one sometimes they are three-pointed, thus : point do they approximate.

But still there is one important distinction; sponges differ from plants, as do all animals, in the chemical compon

or four-pointed, ents of their substance. Azote, or nitrogen, enters as an essential element into the composition of animal matter; hydrogen into that of vegetables, carbon and oxygen being common to both. Tested Multitudes of spicula are placed longiby chemistry, the sponge is truly animal; tudinally around the internal canals of that is, a living animal jelly, investing a which they form the walls; they may be curious frame-work, which it elaborates obtained by washing a sponge, of which and builds up, and to which, as it grows, the animal matter is decomposing, or by it is perpetually adding. Sponges exhibit fusing it before the blow-pipe: they are a great variety of forms, and often the mostly found to consist of silica or flint, most fantastic shapes. Fixed plant-like and minute as they are, are capable of to the rock, they festoon the deep sea scratching glass. In the genus Tethya, caves; they line the walls of submarine the framework consists almost entirely of grottoes, and hang as grotesque ornaments silicious spicula, and quantities are found from the roof; some like inverted goblets, in the ashes of spongia fluviatilis spongia aptly termed Neptune's drinking cups; tomentosa, and other allied species. some like fans, some like globes, and A small portion of silica has been deothers like intertwined branches of un

tected in the ashes of the common sponge, couth growth.

as one of the constituents in the composiThe common sponge of commerce is tion of its elastic fibres. It appears, moreprocured in the Mediterranean, and was over, that the proportion of silica inwell known to the ancients, who applied creases according to the firmness of the it to the same purposes as we do at pre- fibres of sponge, and that where these sent. They used it also as a soft and are elastic, animal matter predominates. elastic lining for their heavy brazen hel- The forms of the spicula are constant in mets. We shall not recapitulate our ob- every species, and consequently become

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tests in their identification. In some rigid texture. They often grow in places species, the spicula are calcareous; and which the returning tide leaves dry; but whether calcareous or silicious, they as- their congenial abode is in sheltered and sume the forms which the crystals of tranquil spots, in caves, and fissures of lime and silica present under ordinary rocks, where the water, never ruffled by circumstances.

the storm, is “deeply, darkly, beautifully Though every species of sponge has its blue." All sponges, however, are not characteristic figure, still no two indi- marine; several species are peculiar to viduals of the same species agree in ex- fresh waters, and constitute the genus ternal form, or in the number and pre- Spongilla of Lamarck, and Ephydatia of cise directions of their large canals. Among Lamouroux. the higher animals, as we know every The spongilla fluviatilis is not uncomspecies resembles the rest of its species, mon in clear rivulets, adhering to stones: in the form of the limbs and teeth; in the its colour varies from bright green to length and figure of the ears, tail, muzzle, pale brown, and, besides, changes accordetc.; and also in the arrangement and ing to the action of light. From this colouring of the hairs, spines, scales, or circumstance, an able writer in the feathers. But this definiteness of figure, Magazine of Natural History, inclines involving a constancy in the number and to the opinion that these fresh water arrangement of composing parts, dimin- sponges are really within the pale ishes in degree as we verge towards the of the vegetable kingdom, and conselower groups, and when we arrive at the quently that marine sponges are so. (See lowest, we see diversity in the midst of article on the action of light upon the

colour of the river sponge, by John Hogg, Nor can we be surprised at this, when M.A., F.R.s., L.s.) Dr. George Johnwe reflect

upon

the condition of the nerv- son, in his Natural History of British ous system, and upon the vital laws by Zoophytes, advocates the same theory, which these beings are governed. No on the grounds that sponges two sponges of the same species corres- animal structure or individual organs, and pond in figure, or in the number of their exhibit no one function usually supposed canals; for the latter multiply as the to be characteristic of that kingdom.” animal increases, and circumstances in- On the other hand, Ellis, (see Linnean fuence developement in one part more Correspond. vol. i.,) whose labours on than another.

zoophytes were rewarded in 1768) by But still though this be the case, there the Royal Society, the Copley medal being are limits to this law of variation, so that awarded to him, states as the result of no species puts on the appearance of his investigations, that the whole sponge another. The cup sponges never ap- is an animal, through the pores and canals proach such as are branched, nor these, of which the water circulates; and this such as resemble tufts of moss; though is the belief of most naturalists and phytwo cup sponges are never precisely of siologists of the present day. the same outline, nor two branched

Sponges occur abundantly in a fossil sponges of the same shape, and with the state, both in the chalk strata, and in the same figure and proportion of their rami- deposit termed “ crag,” of Norfolk and fications. In these particulars, sponges Suffolk. Professor Phillips observes, that resemble plants and trees. We all know the interesting remains of sponges an oak by its specific characteristics; but nowhere so well developed as in England, no two oak-trees have the same contour of and perhaps, nowhere in England so well stem, number and direction of branches, as in Yorkshire.

On the shore near or number of leaves. Thus it is, that Bridlington, they lie exposed on the cliffs while they preserve their genuine specific and scars, and being seldom enclosed in characters, they luxuriate in individual flint, allow their organization to be studied differences.

with the greatest advantage." M. Sponges are universally distributed through the ocean ; they are to be met with on every rocky coast from the polar circles to the meridian. It is, however, in the intertropical latitudes that they EUROPE belongs almost entirely to the display gigantic forms, and strange or northern temperate zone,

Its most imgrotesque figures; in the colder latitudes portant countries lie between the fortieth they are smaller, and

firmer and more

and sixtieth degrees of north latitude.

are

EUROPE HAPPILY SITUATED.

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