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of lead in solution in the gallon of water, sufficient to produce injurious effects, depends very much on the individual constitution and on the length of time that the water continues to be used. Dr. Penny, professor of chemistry at Glasgow, cites an instance of the health of a whole community being deranged by water containing only of a grain of lead to the gallon; and also quotes the conclusion of Dr. John Smith of Aberdeen, that the limit of manifestly deleterious action would seem to be somewhere between and of a grain. An interesting case is report ed of the lead disease attacking a large number of the household of the ex-royal family of France in 1848, while they resided at Claremont, Surrey, Eng. The spring that supplied the palace had been selected for the purity of its water, and lead pipes had been laid 30 years previously to the palace, 2 miles distant. Four members of the family manifested some symptoms of poisoning after 5 months' use of the water, and in 7 months 13 persons were alarmingly affected. The water on examination was found to contain one grain of lead per gallon.-Although the testimony of the highest medical authorities weighs strongly against the use of lead pipe, it is not likely to be abandoned until some substitute is found equally cheap that possesses its peculiar advantageous properties. Little confidence is felt in the attempts that have been made to shield it by an internal coating of some innocuous substance, which necessarily increases its cost without insuring perfect protection. If it must then be submitted to as a necessary evil, it is important to understand how it may be used with the least risk. The greater danger is in general to be apprehended, the more of the pipe is used, the longer the water is allowed to stand in it before using, and the more the pipes are exposed to the alternate action of air and water as they are filled and emptied. Pipes in the upper parts of buildings are frequently left empty of water by this being drawn off below, and for this reason are more exposed to chemical action than those constantly filled. The first flow of water through any lead pipes that have been left some time without use will wash out the dissolved salts of lead. If this water is allowed to run to waste to the amount of several times the contents of the pipes, that which follows is not likely to contain any injurious quantity of lead. By thus drawing off every morning the water that has stood in the pipes, and then washing them out by the continued flow for a short time, all risk of lead poisoning may be avoided.-The published information on the subject of lead poisoning and the effects of water upon lead is scattered through a vast number of medical and chemical works and reports of sanitary committees. The most important works to consult are Christison on poisons, and L. Tanquerel des Planches on lead diseases, translated from the French by Dr. Samuel L. Dana (Lowell, 1848); and convenient reference may be had to the opinions of a great number of chemists in the "Collection of Re

ports (condensed)," prepared and published in 1859 by Mr. James P. Kirkwood, engineer of the Brooklyn water works.

LEAF, an appendage requisite in the growth and perfection of plants, and of two distinct forms, constituting the organs of nutrition and those of reproduction. The first are the true leaves, the latter are flower leaves. In common usage, by leaves are understood the true leaves or foliar organs; but strictly speaking, the floral organs are leaves also-modifications of the original and typical leaf. This original and typical leaf may be defined as an expansion of the living bark of the stem, sustained by ramified processes of woody fibre called nerves and veins, forming a more or less tough network and a strong material, between and over which the tissue of soft pulpy matter (parenchyma) is spread. By this arrangement leaves can become very diversified in figure and size. The leaf of the great water lily of the Amazon river (Victoria regia) has been known to grow to the diameter of 6 feet, and yet the pulpy tissue which makes up its surface is so delicate and tender, that a straw held 6 inches above and dropped perpendicularly upon it would readily pass through it. This vast area of a substance as tender as that of a blanched lettuce is borne between and over a series of singularly contrived nerves and veins, some of which resemble arched ribs, and in order that the leaf may float they are rendered porous by large interstices; they are armed with fierce prickles to ward off aquatic animals which might injure the foliage by approaching from beneath. Such an expanded surface has been found capable of sustaining a weight of more than 70 pounds if by some mechanical contrivance the pressure is equally distributed. The leaf of the bujoor palm of India (corypha elata) often measures 30 feet in circumference; but growing in mid air, its nerves and veins are strong, stiff, and woody, in fact a series of woody branchlets, which seem to pierce and insinuate themselves into the parenchyma; yet in reality, at first tender and soft as itself, they only harden with their development so as to furnish the needed support to the pulpy parts. In all plants which have leaves there is to be observed an axis of growth or development, which, elongated, becomes what is called their stem or trunk. This axis may be reduced to the simplest point, and yet represent the stem. In the germination of a seed, the axis is that portion between the young descending part called the radicle and the thick fleshy apparatus called the seed lobes seed leaves, or cotyledons. These cotyledons are the first foliar organs; but there is another and accompanying process, called the plumule, which bears leaves more fully developed and of a higher though still provisional character. The angle formed by the insertion of these leaves upon the axis is called the axil, and in such an axil, through every process of vegetation thereafter, the bud which is to produce the next leaf is prepared. The axis and its axillary bud being thus provided for, we

notice that the primary condition of the leaf is that of a little conical body, which pushes out from the axis; but its after form depends upon other considerations. In internal structure, this axis and the seed lobes, or further onward the axis and foliar organs, are the same. The substance of which they are composed is called the cellular tissue. This tissue is in fact a countless multitude of very small vesicles, each possessing a sort of individual life or vegetation, which renders it capable of reproducing itself so as to form many new vesicles. These vesicles are known as cells, and are the most elementary organs of the plant-mere hollow spheres of vitalized matter, having contents capable of such changes as will eventuate in their reproduction. The primary and original form of the cell alters from the sphere to any form required by the circumstances of growth, and hardens into wood and woody fibre, following the same laws as are to be seen in operation in the stem itself. Some forms of plants are so simple that the perfected plant consists of a single cell (protococcus, for example), and the living pulp of a growing leaf may, in somewhat the same sense, be regarded as an aggregated or social condition of unicellular plants destined in such a society for another purpose. From the almost ideal size of the axis, we trace an upward development in the flattened base or lecus of the bulbous roots (improperly so called) of some vegetables, the bulb being in fact a shortened stem ending in a terminal bud, which is made up of the scaly coats enclosing the incipient leaves and flowers. Such being the office of the axis or stem, it is evident that the leaf is dependent upon the original idea of the axis in regard to its form, disposition, and general character. Thus, the structure of a monocotyledonous stem or endogen permits only a limited variation in the form of the leaf, and what are called the nerves and veins of such a leaf uniformly assume either rectilinear or at least parallel curving directions. The venation in the leaves of a dicotyledonous plant or exogen, on the other hand, is more free and unconstrained; and the nerves and veins accordingly ramify into multitudes of very delicate and fine fibres, corresponding somewhat to the mode of ramification of the stem itself into limbs, branches, twigs, and general spray. It is to be observed that the terms veins and nerves in botany have no such meaning as applies to them in zoology, they being merely appearances of such organs, but in fact neither hollow nor fitted as special vessels for the conveyance of sap or of nutritive fluid, any more than other parts of the parenchyma or cellular tissue. So close is their analogy to mere woody, branching threads, and frameworks for the support of the pulpy parts, and so similar to the larger branches of the trunk, that it is asserted that these bundles in the leaves are progressive bundles, and that they are so framed that (regarding the leaf as passing off horizontally from the axis) the oldest parts lie above, the youngest below. In the

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lower part also a combined layer exists in dicotyledons; in the lower part liber bundles accompany the vascular bundles, and in the under part the vascular bundles in relatively thin and flat leaves project above the surface, while the upper part of the leaf appears level. (Schleiden, Principles of Scientific Botany," translated by Edwin Lankester, London, 1849, p. 277.) The young and growing leaf, at first a little conical body, consists of a tender mass of cellular tissue; determinate cords of this tissue harden into fibres, which are the future framework of the entire structure. In some kinds of leaves (especially the parts of the flower) no such fibres occur. The great variety presented by different kinds of leaves in these ramifications of veins is worthy of study. The pulp itself or parenchyma is also developed in the most varied mode; but the general structure is similar in all. It consists of layers of cells placed one above another, in more or less close contiguity, and so as to have some cells which are filled with aqueous juices of a larger and looser arrangement than those which are found near the surfaces. These likewise contain most of the coloring matters that give the green hue to the leaf. In some kinds of leaves the cells are spirally fibrous; others have cells which contain peculiar juices or even crystals; others still, cells which constitute vessels containing fluids of a milky nature, or else receptacles for gum, oil, or resin. Beautifully arranged air cavities and air canals are found in the leaves of some particular plants. The distinct layers of the cellular tissue have also specific purposes. Of these may be mentioned the epidermis or skin, which is the hardening of a delicate epithelium exposed to the atmosphere; the same layer of tissue exposed to continued moisture, as in subterranean leaves and in those which float upon the water, becomes the epiblema, which consists of compact cells without intercellular passages and destitute of breathing pores such as exist in the airexposed surfaces. But while the internal structure is thus in general similar, the external contour is diverse. What may be here styled the forms of leaves constitute an essential element in the classification and description of plants. The several parts of a perfect leaf are the footstalk (petiole), the stipules at its base, and the lamina or blade. These, essential to a perfect leaf, may be individually wanting; as there are leaves which have no stipules, others which have no petioles, and others in which the blade is suppressed. The blade occurs more than once in some sorts of leaves, and the leaf is then compound; or if it is a single expansion without any intervening space or joint, it is simple. Some leaves are so very compound as to be made up of 80 little blades. As we have already noticed, the venation of the leaf is remarkable for its variety, and it alone would furnish a very good guide in distinguishing and arranging different species of some families of plants. The termination of the fibres which compose the veins is to be found in the edge of the pulp, at

the circumference; and whatever is the shape of the leaf, the outline appears to be determined by the development of the parenchyma between the veins. De Candolle has illustrated this by showing how, if the lateral veins are all short and of equal length, the leaf will be narrow or linear; if those of the middle are sensibly longer than those of the base and apex, the form will be elliptical, oblong, or even orbicular; but if the veins are longest at the base and gradually diminish toward the top, the leaf will be ovate, or if the longest veins are beyond the middle, obovate. The presence of a greater or less quantity of pulpy matter investing the branching development of the veins would cause a wider or narrower separation between each, as these remained in their original plane of growth or anastomosed with each other. Accordingly, in a capillary leaf we see the veins thus widely separate from the first and remaining so. These leaves are often to be found in plants submerged for a part of their existence, like the water ranunculus; if more pulpy matter were developed on each edge of the veins, the space between might become entirely filled, and an entire outline be the result. If however the pulp does not quite occupy all the spaces, the leaf may be bordered with rounded notches or scallops (crenate); or cut into sharp tooth-like jags (serrate); or coarsely toothed (dentate); or more coarsely toothed in consequence of rather more deficiency of pulp (sinuate); or still more deficient (lobed); or the blade may be cut down into sharp narrow incisions (cleft); or the incisions may extend almost through (parted), or to the very midrib or petiole, and form on each side of it distinct leaflets (divided). When these several leaflets are jointed to the main stalk, they follow the same law that obtains in larger and entire leaves, each leaflet falling separately either just before or at the time of the fall of the leaf itself; and such an arrangement of leaflets on a common petiole is called pinnate. By further divisions of each pinna the leaf itself may be bipinnate, tripinnate, &c. The leaves of many plants in which the blade is still present are reduced to mere spines, as in the cactuses; or to mere scales, as in the dodders; or assume the forms of broader scales, that are thickened but taper to a sharp point, as in the cedar and juniper; or thickened, narrow, long, and needleshaped, as in the larch and pines. The leaves of many species do not develop any blade whatever, and present flattened petioles in their place, like the acacias of New Holland; or even, extending the mere petiole beyond its typical form in the leaf, it becomes a filamentous tendril fit only for support by winding its extremity around other objects. Other peculiarities may also originate through this development or suppression of the parenchyma in different portions of the growing leaf; so that it may grow into a globular, ovate, prismatic, or flattened blade, as the cells accumulate in the middle rather than at the edges; in like manner, by the thickening of the

edges beyond that of the middle, the plane or flat-surfaced leaf may assume concave forms. This thickening of the parenchyma gives rise in some leaves to a fistulose shape, as in the onion, where, the circumference growing faster than the centre, the leaf becomes hollow by the bursting of the cells in the central portion, and by its inability to make good the void by supplying new pulpy material. Other singular forms of leaves are owing to another peculiarity in the nature of the parenchyma, which is that of a natural grafting or cohesion of the edges of the same organ. Thus in the stipules, which resemble little blades and which are situated at the base of the footstalks, we see that, although often distinct and separate, as in the heartsease, yet they cohere sometimes at their edges and surround the axis whence the leaf which bears them springs. In polygonum these stipules become perfect sheaths, and are called ochrea; in the rose they grow to the edges of the petiole, of which they become a thin leafy margin; while in some species of astragalus they unite and meet on the opposite side of the leaf. The petioles of some species of plants possess a similar power, as we see in the flattened united edges of the leaf of the sidesaddle flower of our swamps (Sarracenia), where this folding together of the two edges produces a sort of hollow goblet-shaped figure surmounted by the blade of the leaf hanging down like a lid; also in the pitcher plant of India (nepenthes), where the petiole is partly round and partly expanded, but rolled into the form of a pitcher, the blade fitting closely to its aperture or mouth. Sometimes, however, the reverse occurs, as in dischidia, where the opening of the pouch is downward and toward the base of the leaf; while in Marcgraavia the pouches are formed by the cohesion of little leaves (bractea) which are borne at the base of the flowers. This power of cohesion also exists in the blade itself, as we notice in perfoliate plants, where the bases of two opposite leaves engraft so completely at the edges as to surround the stem and cause it to appear as if it had forced itself through the centre of a single and entire leaf; as in the honeysuckle (Lonicera) and the cup plant (silphium perfoliatum).—The office which the leaf performs in the economy of vegetation is of the highest importance. The conversion of inorganic, dead, mineral matter into living substance, to make new depositions of wood, to produce seeds or fruits as well as a variety of valuable secretions, belongs mainly to the foliage or leaves. One of the means is the exposure of as large a surface of the plant as is possible and as is requisite to the air and light. In a large elm tree it has been calculated that there existed in a single summer about 5 acres of foliage. Such an apparatus is a great natural laboratory, through which the sun's rays enable the living plant to originate peculiar chemical combinations and to increase its bulk in new forms. The importance of the foliage to the healthy condition of the plant is equally seen in every

stage of its growth; and, as has been stated, the floral organs are only modified forms of foliage suited to the purposes which they are to subserve. Every horticulturist knows how essential it is to secure a large, healthy, and abundant foliage, and how injurious is any improperly applied pruning to the maturation of the fruit. Beside this office thus imposed upon the leaf in the purposes of the growth of the vegetable, the presence of plants acts constantly and favorably upon the health of animals, rendering the atmosphere pure and salubrious, or else serving to condense the vapors which would otherwise be lost. Thus the beauty, the coolness, and the refreshing shade, which trees planted in cities afford, are not the only benefits to be derived; but every green and living leaf becomes in such close and pent-up places an ever useful though humble minister, to render the atmosphere fitted for healthy respiration; and this it does by the absorption, for its own peculiar nutriment, of deleterious gases, and by giving out again others which are requisite.

LEAGUE (Sp. legua; Fr. lieue), a measure of length used for estimating distances at sea, and by European nations upon land also. The nautical league is of a degree, or 3 equatorial miles, or 3.457875 statute miles. The land league in England is 3 statute miles. In France it has been used for different distances, as the legal post league, 2.42 English miles, and the league of 25 to the degree, or 2.76 English miles. The Spanish league is still more variable, sometimes 17 and again 174 being reckoned to the geographical degree. Upon the modern roads 8,000 Spanish varas, or 7,416 English yards, are estimated one league. The term is supposed by some to have come from the Celtic leach, a stone; and by others the Gallic leuca, league, is traced to the Greek devkos, white, white stones being used by the Gauls to mark distances upon the roads.

LEAKE, a central co. of Miss., traversed by Pearl river; area, 576 sq. m.; pop. in 1850, 5,533, of whom 1,549 were slaves. It has a rolling surface and a light, sandy soil. The productions in 1850 were 180,637 bushels of Indian corn, 46,534 of sweet potatoes, 70,040 lbs. of rice, and 1,644 bales of cotton. There were 5 grist mills, 19 churches, and 342 pupils attending public schools. Capital, Carthage.

LEAKE, SIR JOHN, an English admiral, born in Rotherhithe, Surrey, in 1656, died in Greenwich, Aug. 1, 1720. He first distinguished himself in the fight with Van Tromp in 1673, and again by conveying relief to the starving garrison of Londonderry, and thus compelling the enemy to raise the siege. In 1702, during the war of the Spanish succession, he was promoted to the rank of commodore, and appointed to the command of a squadron, with which he rescued Newfoundland from the French. For these services he was made rear admiral, and soon after vice-admiral of the blue and knighted. In 1705 he constrained the French and Spanish to abandon the siege of Gibraltar; in 1706 relieved

Barcelona, and captured Carthagena; and subsequently reduced the Balearic isles and Sardinia. After the relief of Gibraltar and the reduction of Carthagena, he was made vice-admiral of the white, and presented with £1,000 by the queen; in 1707 he was appointed commanderin-chief of the fleet, and in 1709 rear admiral of Great Britain and a lord of the admiralty; and on retiring from active service, in the reign of George I., had a pension of £600 settled on him by parliament. He represented Rochester in parliament for several years.

LEAKE, WILLIAM MARTIN, an English officer and Philhellenist, born in 1777, died in Brighton, Jan. 6, 1860. In the early part of his military career he was employed on special missions to Asia Minor and other parts of the East, and devoted himself to the exploration of Greece. He rose to the rank of lieutenant-colonel, but retired from the service in 1823. He was a zealous champion of the national independence of the Greeks, and endeavored to procure help for them from the English government during the conflict with Turkey. In 1814 he published his "Researches in Greece;" in 1821, his "Topography of Athens" (2d ed., 1842); in 1824, the "Journal of a Tour in Asia Minor;" in 1827, in concert with the Hon. Charles Yorke, "Notices of the Chief Egyptian Monuments in the British Museum;" in 1830, his "Travels in the Morea;" in 1835 and 1841, his "Travels in Northern Greece;" in 1846, his "Peloponnesiaca, a Supplement to the Travels in the Morea;" and in 1854, “Numismatica Hellenica," the appendix to which was published in 1859, shortly before his death. He was assisted in this work and many of his other labors by his wife, who was a daughter of Sir Charles Wilkins, and whose first husband had been Mr. Marsden of the English admiralty. He also wrote several political works on Greece. Prominent among them is his "Historical Outline of the Greek Revolution" (1826).

LEAMINGTON, or LEAMINGTON-PRIORS, a town and watering place of Warwickshire, England, on the river Leam, 20 m. S. E. from Birmingham; pop. in 1851, 15,692. It is one of the handsomest towns in England. Its only manufacture is that of gloves. Its prosperity and importance have mostly arisen from its mineral springs, which are of three kinds, sulphurous, saline, and chalybeate. The surrounding country is picturesque and beautiful, and the castles of Warwick and Kenilworth, as well as Stratford-upon-Avon, are not far distant. LEANDER. See HERO.

LEAP YEAR. See CALENDAR.

LEAR, TOBIAS, an American diplomatist, born in Portsmouth, N. H., about 1760, died in Washington, D. C., Oct. 11, 1826. He was graduated at Harvard college in 1783, and in 1785 became private secretary to Gen. Washington, by whom he was always treated with great courtesy and regard. For several years he attended to the details of Washington's domestic affairs, and was most liberally remem

bered by him in his will. In 1802 he was consul-general at St. Domingo, and afterward consul-general at Algiers and commissioner to conclude a peace with Tripoli. He discharged this latter duty in 1805 in a manner which gave umbrage to Gen. Eaton, who in concert with Hamet Caramelli, the deposed bey, had gained important advantages over the reigning Tripolitan sovereign. It was thought that to accept terms of peace at this juncture was to throw away the fruits of hardly earned success; but Mr. Lear's conduct was approved by his government, though much blamed by a portion of the public. He returned shortly after to the United States, and at the time of his death was employed in Washington as accountant of the war department.

LEARCHUS, a Greek sculptor of Rhegium, in southern Italy, who flourished probably be tween 700 and 650 B. C. He belongs to the semi-mythical Dædalian period, and the accounts of him are so vague and confused that he may be considered almost a mythical personage. Pausanias mentions a statue of Jupiter, attributed to him, in the brazen house at Sparta, which was considered the most ancient work of the kind. It was made of hammered pieces of brass riveted together.

LEASE, in law, the contract whereby one party (the lessor or landlord) transfers to another party (the lessee or tenant) the use and possession of real estate. The word is sometimes used also to designate a contract for the letting and hiring of personal property. No certain words or forms are necessary for this purpose; but a lease must describe the premises to be demised with an accuracy that is sufficient for certain identification; and there are words which, being usually employed, have now a very definite meaning, as house, farm, land, and the like. Any inaccuracies or uncertainties as to names, dimensions, locations, amounts, or terms, may be explained if the other parts of the instrument suffice to make them certain. As a general rule, they may be explained by evidence outside of the contract, provided this evidence neither varies nor contradicts the written contract. If the uncertainties cannot thus be cured, they may be rejected, if they leave behind them a good and sufficient instrument. Generally, any thing, whether real or personal, which is hired to be used, carries with it all the appurtenances and accompaniments already connected with it, and proper or necessary for that use of it. We will in this article consider: 1, the right and obligation of the lessor; 2, those of the lessee; and 3, some special rules of law applicable to leases. If the lease be under seal, there is an implied covenant of good title in the lessor, and in all leases there is one of quiet enjoyment by the lessee. If the lease contain an express covenant of renewal, on reasonable terms, which do not imply perpetuity, the law enforces them. But a lease for 6 years, with a covenant to renew "on the same terms," means the same terms excepting

the covenant to renew, which will be omitted; for otherwise this covenant to renew would amount to a perpetuity, which the law prohibits. An important practical rule is, that the landlord is under no obligation to repair the premises, without an express covenant to that effect; and it seems to be the decidedly prevailing rule, that the uninhabitableness of the premises is no defence against a claim of rent. Even where the landlord covenants that the premises are in good repair and that he will keep them so, it has been held that the tenant must still pay his rent, however out of repair the premises may be, and seek his compensation by claiming damages from the lessor; but this is not certain. In England the law is very severe against the tenant, not permitting him to vacate the lease unless for some positive and actual wrong doing of the landlord, and not obliging the landlord to inform the lessee of objections or defects, however serious and incompatible with use. But we doubt whether this be law here.-The tenant is bound to pay his rent as agreed on, but not to pay the taxes unless the lease so specifies; but this may be inferred from an agreement that the lessee shall pay his rent "free from taxes and charges," or "a net rent," or any similar phraseology. In general, if the lease does not contain a clause giving the lessor a right to reënter and oust the lessee on his failure to pay rent, the lessor has no such right. And if there be such a clause (as is commonly the case in American leases), the law is exceedingly exact and punctilious as to the exercise of this right of reëntry. That is, to justify it, a demand must be made for the rent due, and of the precise sum, on the precise day when it is due, at a convenient hour before sunset, and at the very place where it is payable if one be specified, or otherwise at some accessible, conspicuous, and noticeable place on the premises. Without express agreement, a tenant is not bound to make repairs. It has been sometimes held, however, that he was bound to make such repairs as his own use of the house causes to become necessary, or such as are called for by some accident and are required to prevent the premises from becoming untenantable. Generally, an outgoing tenant should leave the premises wind and water tight, but is not bound to any ornamental repair, unless his covenants require this of him. If the tenant agrees to make repairs, and to leave the premises in good repair, he is not justified in not doing so by the fact that the premises were not in good repair when he took them. If, with no obligation on his part to repair, he chooses to repair, the lessor is not bound to repay him unless he promises so to do. It is important to know, that if a lease contains a covenant on the part of the lessee to keep the premises in repair, and to return them in good repair, he must not only repair if injured by a fire, but rebuild if the house is burned down, unless it be done by the act of God or of the public enemy. And if there be no such clause, although the lessee is

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