the seeds gradually decrease in number till they altogether disappear. Thus the oranges we esteem the most are the produce of aged trees; those we consider least palatable are obtained from young wood. The best oranges are imported from the Azores and from Spain, but Portugal, Italy, Malta, and other places, supply those of good quality. The trees in the orange gardens of the Azores are magnificent, and may be seen at the proper period bending under the weight of the luxuriant fruit. The shape appears like that of a shrub with many stems springing from the ground, or with one short stem immediately dividing, and of a clean grey tint. The orange gardens of St. Michael are of large extent, always encircled by a wall fifteen or twenty feet high, and within a thick plantation-belt of the faya, cedar, fern, and birch, which protects the trees from the sea breezes. It is not easy to conceive the rich appearance of these gardens during the principal fruit months, when the emerald tints of the unripe, and golden hue of the mature fruit, mingle their beauties with the thick dark foliage of the trees, while the bright odoriferous blossom diffuses a sweetness through the surrounding neighbourhood which is quite delicious. In some instances, the gardens overhang the sides of a glen or ravine, and intermingled with the lofty arbutuses, the trees display their charms to even greater advantage. The plan usually adopted for increasing the number of the trees is by layering. The young plants are bent at the lower end into the ground, and covered with soil until the roots begin to strike, when they are separated from the parent stem, and planted in a small excavation about three feet deep, which has been prepared for them. They remain thus situated till the tender trees are sufficiently strong, and when they are so, the plantations immediately around them are removed, and each one begins to shoot up and flourish without further care, beyond occasionally tarring the stem to avoid the attacks of insects; they then spread out with all the fresh luxuriance of the chestnut tree. The plan of raising trees from seed is seldom adopted in the Azores, as their growth is much retarded by this means, though there is an advantage possessed by them in being far less liable to the inroads of a worm which frequently attacks the roots of the layered trees. The seed of the Seville orange, with the sweeter kind grafted upon it, is said to | produce fruit of the finest flavour. Seven years are required before they attain a good bearing condition, and soon after arriving at full growth each will produce on an average from twelve to sixteen thousand oranges, and even a much larger number. When the trees have blossomed, the forthcoming crops are purchased by the merchants, running all the risk attendant on the casualties to which the fruit is subjected. A continuance of cold north or north-easterly winds, a violent storm, or the attacks of insects will not fail to destroy them, and perhaps in a single night a whole crop may be swept away. It is, therefore, a matter of much speculation with the buyer, who, however, seldom makes his own calculation of the probable amount of fruit the gardens will produce, but leaves it in the hands of the "professionals." These are men who gain their livelihood by the valuation of crops, and such is the accuracy they attain, that by once traversing a plantation, and giving a general glance at the trees, they are able to state, with astonishing correctness, on what number of boxes the merchant may calculate. The fruit is not ripe till March or April, and as that which falls is never sent to England, but suffered to rot on the ground, or sold at a mere trifle, the supply obtained by the children is very great. Those of Villa Franca have a jaundiced appearance, looking, it is said, as though saturated with orange-juice. The picking of the fruit is sometimes performed by children, scores of whom are to be seen scattered among the branches, putting the produce into small baskets, laughing, hallooing, singing, and playing pranks with one another at the same time, as though it were some amusing game in which they were employed, rather than a laborious task. Not unfrequently the weight of the little urchins overturns the trees, in consequence of the lightness of the soil, and the small depth to which the roots proceed. Their season of usefulness, however, is by no means passed, for though lying on the ground, and continuing so for years, the produce is abundant. When the different arrangements for packing the fruit have been made, and a pile of fresh fruit collected, the people take their positions in different places, laughing and joking with each other as the labour proceeds, while a party of children, whose business it is to prepare the dry calyx-leaves of the Indian corn, commence their work. A little fellow now gives one of these husks to a labourer who sits on the ground, and he rapidly snatching it from him, wraps the orange in it, and it is passed on by an intermediate labourer to the packer, who places it in the orange-box with amazing rapidity. A second and a third are taken in the same manner, and with that speed which long practice is calculated to produce, the feeders supplying him till the chest is full, and prepared to be nailed down. The carpenter then receives it from two men, who bending over the orange chest several boards, they are secured with a a willow band, and the ragged ends sawn off. It is then removed on the back of an ass, to the port where the vessel lies which is to carry it away. The boards which form the top of the orange-box seem unable to afford that protection to the fruit which is desired. They are certainly well adapted to spoil the contents; for the flattening and squeezing of the fruit is never beneficial, but the advantages on the other hand overbalance this difficulty. One reason is, that the duty to be paid in England is calculated according to the size of the box, and, consequently, the more oranges that can be squeezed in, the less duty is paid. Another inducement is, that the wholesale dealers in London, Liverpool, and other commercial cities, are enabled, by this mode of packing, to remove a couple of hundred oranges before forwarding the boxes to their country customers, as full ones, which they perhaps may be, from the oranges squeezing out to their original size, on the removal of the pressure. A proprietor of orange gardens in the Azores adopted a plan of sending his fruit in square boxes, less tightly packed; but finding his customers displeased by it, he relinquished the attempt. It is doubted by some whether the orange is a native of China, as it is not mentioned by Marco Polo, who is very circumstantial in his description of the country. Yet the earliest European visitors, the Portuguese, discovered it there; and John Bell was told by one of the missionaries, that the tree was still standing at Canton, from which the missionaries sent the seeds which first appeared in Europe. The first distinct mention of the tree of which information can be obtained, is by the Arabs. It is noticed by Avicenna; and Galessio, in whose "Traité du Citrus," published in Paris, in 1811, the history of this fruit was first carefully traced, states, that when the Arabs penetrated to India, they found the orange tribe there farther in the interior than Alexander had advanced. They were brought from thence by two routes: the China, or sweet oranges, came through Persia to Syria, and thence to the shores of Italy and the south of France; and the bitter oranges, called in the commerce of England Seville oranges, by Arabia, Egypt, and the north of Africa, into Spain. At the period when the Europeans first visited the Levant in great numbers, that is, during the time of the crusades, oranges were found abundantly in that country. Though in reality cultivated trees, their number, and the beauty and excellency of their fruit, caused the romantic adventurers to believe that they were indigenous. The fables of the profane writers helped further to confirm this opinion; and as the oranges were the colour of gold, it required but a slight stretch of the imagination to make them the golden apples of the garden of the Hesperides. The first oranges were brought into England by sir Walter Raleigh; and it is stated, that sir Francis Carew, who married the niece of sir Walter, planted their seeds, and they produced the orange trees at Beddington, in Surrey, to which allusion is made by bishop Gibson, in his additions to Camden's "Britannia," who speaks as having been there in 1595. As these trees afterwards produced fruit, they could not, as professor Martyn justly observes, have been raised from seeds; but they may have been brought from Portugal or Italy, as early as the close of the sixteenth century. The trees at Beddington were planted in the open ground, protected by moveable covers from the inclemency of the winter months. In 1738, they were surrounded by a permanent inclosure, like a greenhouse, but they were all destroyed by the great frost of the following year, though perhaps aided by the confinement and damp of their intended protection. At Hampton Court, there are many orange trees, some of them stated to be three hundred years old. They are generally removed into the open air about the middle of June, when the perfume of their blossoms is delightful. In a few gardens in the south of Devonshire, orange and lemon-trees may be seen, trained as peach-trees against walls, sheltered with straw mats during the winter. The fruit of these is stated to be as large and fine as any in Portugal.* Though the orange is the natural produce of other climes, the people of this country seem to possess all its advantages. It is to be purchased among the commonest of our domestic fruits, offering its grateful juice even to the poorest of the community. The exports of oranges from the Azores are chiefly to England, and in ordinary years it amounts to about 130,000 boxes, each of which contains about 500; there is an annual supply of 65,000,000 from the western isles alone. The orange-trees of Portugal, too, are well known. It is a goodly sight to see There are annually exported from that country nearly 100,000 chests of oranges and lemons, while Spain exports about half that amount. In 1838, England imported little less than 300,000 chests. The uses of the orange are many. Not only is it considered an excellent addition to the dessert, but it is also employed in medicine, particularly the Seville orange, which has a bitter rind. The juice is a grateful acid liquor, which, by allaying thirst, proves of much use in all febrile and inflammatory disorders. It is of great advantage in scorbutic complaints; and the outer rind of the Seville orange is used as a stomachic. Other medicinal virtues are also ascribed to the various productions of the orange-tree, the efficacy of which are, probably, not so well understood. F. THE MICROSCOPE. THE fallibility of human judgment is never more clearly shown than in many of the predictions unhesitatingly made and authoritatively enforced, in relation to any new scientific discovery, or its application to the onward progress of human knowledge, or to the wants and comforts of mankind. We do not allude to the mere ignorant assertions of ignorant and self-sufficient men, who appear to regret and endeavour to oppose every forward step in civilisation; and who, despite the constant failure of their prophecies, still receive any scientific novelty with incredulity, or treat its * Horticultural Transactions. discoverer with contempt and scorn: but we speak of the assertions made by men whose whole lives have been devoted to philosophical inquiry, and whose minds have therefore been matured by deep study and a constant observation of those phenomena concerning which they so unhesitatingly and so incautiously prophesy. Numberless examples of this fact present themselves to our recollection; but we will content ourselves with reference to two only. When it was first proposed to substitute gas for oil in the illumination of the streets of London, sir Humphrey Davy asserted that it would be as practicable to cut a slice from the moon, and use it as an illuminating power. And yet but a few years rolled over, before not only the metropolis, but every provincial town had its gas-works and its gas illumination, the hopes of those who had suggested the improvement were fulfilled, -the prediction of the greatest philosopher of that day was but a groundless apprehension. And again, when Transatlantic steam-navigation was proposed, Dr. Lardner affirmed, in the most unqualified manner, that it was impossible that any steam-vessel could traverse the Atlantic. The prediction was scarcely made public ere the task was accomplished.† We are naturally led to these remarks in referring to the history of one of the most beautiful and perfect instruments with which modern science has furnished the philosopher-the compound micro On this subject it may not be uninteresting to add that, during the winter months, 890 tons of coals are used, on the average, per day, by the Metropolitan Gas Companies, for the manufacture of gas; and that, on the 24th of December, seven million cubic feet of gas are consumed in London and the suburbs. We are indebted for this information to a paper read before the last meeting of the Statistical Society, by Mr. Fletcher. + Dr. Lardner's prophecy was delivered before the British Association, and was published in the Athenæum, vol. ix., page 656. He computed that for each horse-power of steam one ton of coals would be required for every 1425 miles. "Taking this as a basis of the calculation," said he, "and allowing one-fourth of a ton of coals per horse-power as spare fuel, the tonnage necessary for the fuel and machinery, on a voyage from England to New York, would be 3.70 tons per horse-power, which, for a vessel with engines of 400 horse-power, would be 1480 tons." Now, as the ship referred to was only wards increased to 1340 tons, the voyage was de. monstratively impracticable. And yet the Great Western completed her first voyage across the Atlantic in fifteen days. Upon after-examination it turned out that, although the computations of Dr. Lardner were correct, his data were wrong. Instead of the 1480 tons, which it was predicted the Great Western would have to burn, she took out only 660 tons, of which only 450 tons were consumed. intended to be 1200 tons burden, which was after scope. For a long period, this instrument was considered a mere philosophical toy, owing to the distance which the light had to traverse, and the consequent increase of the chromatic and spherical aberration; and so impossible did it appear to overcome this difficulty that, within thirty years of the present period, philosophers of no less eminence than M. Biot and Dr. Wollaston predicted that the compound would never rival the single microscope, and that the idea of rendering its object-glasses achromatic was hopeless. Nor can these opinions be wondered at, when we consider how long the achromatic telescope had existed without any attempt to apply its principles to the compound microscope. And if we recollect further the smallness of the pencil required by the microscope, and the enormous increase of difficulty attending every enlargement of the pencil; if we consider further that these difficulties had to be contended with and removed, by operations on portions of glass so small that they were themselves almost microscopic objects; we shall not be surprised that even a cautious philosopher and able manipulator, like Dr. Wollaston, should prescribe limits to its improvement. Such is the picture with which we are presented if we inquire into the use of the microscope thirty years since. Fortunately, however, for science generally, these apprehensions of Wollaston have proved false; undeterred by the assertion of authorities of such eminence, philosophers and opticians have conjointly devoted their energies to a task at first apparently so hopeless, the result of which has been that the improvements thus effected during the last fifteen years have sufficed to elevate the microscope from the useless condition we have described to that of being the most important instrument ever bestowed by art upon the investigator of nature. In almost every department of science are we indebted to it for the extension of our knowledge, and the_verification of previous observation. To the chemist it is of utility in the examination of crystals, and the determination of their angles-to the pharmacist, in the detection of the adulteration of drugs. The physiologist may ascertain the intimate structure of organic tissues in their normal, the pathologist in their abnormal state; the physician may obtain conclusive and satisfactory evidence regarding the nature and seat of disease by the examination of the secretions or excretions of the diseased organs, while in medico-legal inquiries, the microscope again comes to our aid, in detecting the murderer, and rendering him back the poison, grain for grain. To it, recently, has geology been greatly indebted; in the hands of an Owen and a Mantell the microscope becomes an instrument of magic power, by means of which, from the inspection of a portion only of a bone or tooth, the habits of the animal to which it belonged are decided; the colossal reptiles of the ancient earth are revived in all the reality of life and being, and the early formations of our globe decked with their former inhabitants and the vegetation which clothed them long ere man "moved, and breathed, and had his being." But perhaps in the departments of botany and zoology have the most extensive discoveries been effected by this instrument. A new world of microscopic life previously unknown and unsuspected has been disclosed, whose extent and wonders naturally excite in the human mind unbounded astonishment, and increase our reverence for the Great Creator, who, in the organization of these beings of a day, displays design as extensive, and adaptation as complete, as in the structure of man himself. An extract from the opening remarks of one of the works before us, will convey some faint idea of this microscopic world : "Wherever we turn, within the precincts of our own homes, in meadow or moorland, hill or forest, by the lone seashore or amidst crumbling ruins-fresh objects of interest are constantly to be found; plants and animals unknown to our unaided vision, with minute organs perfectly adapted to their necessities; with appetites as keen, enjoyments as perfect as our own. In the purest waters, as well as thick, acid, and saline fluids, of the most indifferent climates-in springs, rivers, lakes, and seas-often in the internal humidity of living plants and animals, even in great numbers in the living human body-nay, probably, carried about in the aqueous vapours and dust of the whole atmosphere, there is a world of minute, living, organized beings, imperceptible to the ordinary senses of man. In the daily course of life, this immense mysterious kingdom of diminutive living beings is unnoticed and disregarded; but it appears great and astonishing, beyond all expectation, to the retired observer who views it by the aid of the microscope. In every drop of standing water he very frequently, though not always, sees by its aid, rapidly-moving bodies, from 1-96 to less than 1-2000 of a line in diameter, which are often so crowded together, that the intervals between them are less than their diameter. If we assume the size of the drop of water to be one cubic line, and the intervals, though they are often smaller, to be equal to the diameter of the bodies, we may easily calculate, without exaggeration, that such a drop is inhabited by from one hundred thousand to one thousand millions of such animalcules; in fact we must come to the conclusion, that a single drop of water, under such circumstances, contains more inhabitants than there are individuals of the human race upon our planet. If, further, we reflect on the amount of life in a large quantity of water, in a ditch or pond, for example, or if we calculate that, according to many observers of the sea, and especially of its phosphorescence, vast tracts of the ocean periodically exhibit a similar development of masses of microscopic organized bodies, even if we assume much greater intervals-we have numbers and relations of creatures living on the earth, invisible to the naked eye, at the very thought of which the mind is lost in wonder and admiration. It is the microscope alone which has enabled close observers of nature to unveil such a world of her diminutive creation, just as it was the art of making good telescopes which first opened to their view the boundless variety, and all the wonders of the starry firmament."-Microscopic Manipulation, pp. 13,.14. Who can wonder, then, that this world of microscopic life should, upon its first discovery, have been represented by fanciful writers as a world of spirits, peopled by forms not to be compared with those of the visible world; sometimes horrible, sometimes strangely distorted, neither properly animate, nor yet properly inanimate. Some have represented them as the wanton sport of the creative energy of nature (lusus naturæ ;) and even in 1820, an otherwise respectable writer described in detail the magic powers with which some of these forms were said to be endowed. It is not, however, merely the singularity and minuteness of their form that have excited the greatest interest, but the wonderful physiological properties_ascribed to the Infusoria by different observers have attracted the at tention of all the friends of science, and of the most learned and profound inquirers, from Liebnitz and Boerhaave down to the present time. Before we proceed to speak of the revelations of the microscope, it will be interesting to take a retrospective glance at its history, which, like that of many other valuable inventions, is veiled in considerable obscurity by the lapse of time. It appears certain that the ancients were acquainted with the microscope, in one at least of the simple forms now known, from a passage in Seneca. Amongst the moderns (for during the middle ages it appears to have been entirely lost) the honour of its discovery has been claimed by many individuals. By Huygens, the celebrated Dutch mathematician, its invention is attributed to one of his countrymen, Cornelius Drebell. But it is asserted by Borellus, that Jansen, the reputed contriver of the telescope, was its inventor, and that he presented some such instrument to Prince Maurice, and Albert, archduke of Austria. This instrument was six feet in length, and consisted of a tube of gilt copper, supported by thin brass pillars in the shape of dolphins, on a base of ebony, which was adapted to hold the objects to be examined. Of the internal construction of this microscope we have no account, though there is reason to believe that it was nothing more than a telescope converted into a microscope. For ourselves, we are inclined to give to Jansen the merit of having invented the microscope from this very testimony of Borellus, who, in a work published in 1655, has adduced a great deal of evidence connected with the invention of the telescope and microscope. He brings forward five different testimonies, and a letter from William Boreel, envoy from the states of Holland, which throw considerable light on the subject. Boreel was intimately acquainted with Zaccharius Jansen, and had frequently been in his father's shop. He had often heard that the Jansens were the inventors of the microscope, and having been in England in 1619, he saw in the hands of his friend Cornelius Drebell the very microscope which Zaccharius Jansen had presented to prince Maurice, and Albert, archduke of Austria. Cornelius Drebell, therefore, who has commonly been considered as the inventor of the microscope, appears to have derived this honour * De Vero Telescopii Inventore. |