Page:Encyclopædia Britannica, Ninth Edition, v. 14.djvu/459

 L E M L E M 439 greasy stcaroptene, apparently identical with the bcryapiene ob tained from the essential oil of the Bergamot orange. The chief constituent of oil of lemon is the terpene, C 10 H 16, boiling at 348 8 Fahr., which, like oil of turpentine, readily yields crystals of terpin,C] H 16 30H 2, but differs in yielding the crystalline compound, C 10 H 1G + 201, oil of turpentine forming one having the formula C i H 16 + HCl. Oil of lemons also contains, according to Tilden, another hydrocarbon C 10 H 16, boiling at 3 20 Fahr. , a small amount of cymenc, and a compound acetic ether, C 2 H 3 O.C 10 H 17 O. The natural essence of lemon not being wholly soluble in rectified spirit of wine, an essence for culinary purposes is sometimes prepared by digesting 6 ounces of lemon peel in one pint of pure alcohol of 95 per cent. , and, when the rind has become brittle, which takes place in about two and a half hours, powdering it and percolating the alcohol through it. This article is known as lemon flavour. The name lemon is also applied to some other fruits. The Java lemon is the fruit of Citrus javanica, Bl., the pear lemon of a variety of Citrus Limetta, and the pearl lemon of Citrus margarita. The fruit of a passion-flower, Passijiora laurifolia, is sometimes known as the water-lemon, and that of a Berberi- daceous plant, Podophyllum peltatum, as the wild lemon. In France and Germany the lemon is known as the citron, and hence much CDnfusion arises concerning the fruits referred to in different works. The essential oil known as oil of cedrat is usually a factitious article instead of being prepared, as its name implies, from the citron (Fr. cedratier). An essential oil is also prepared from Citrus Lumia, Risso, at Squillace in Calabria, and has an odour like that of Bergamot but less powerful. The juice of the sweet lime (Citrus Limetta, Kisso), which is now largely substituted in the British navy for lemon juice for the pre vention of scurvy, is imported principally from Montserrat. This island, although it only contains an area of 47 square miles, possesses the most extensive and best cultivated plantations of limes, Citrus Limetta, in the world. About thirty years ago a small plantation was commenced in the island by Mr Burke, at considerable outlay and with no prospect of an immediate return, and hence was not at first attended with success. But the Montserrat Lime Juice Co. now owns 600 acres, bearing 120,000 trees. Although the fruit is collected all the year round, it is never gathered from the trees, but gangs of women labourers are sent out about 5 o clock in the morning to collect all the fallen fruit. These when brought home are immedi ately sorted into sound and unsound fruits. The sound fruits are then bruised by hand in an ecuclle, a saucer-like vessel with a num ber of projections arising from its bottom ; by this means the oil cells in the rind are ruptured and the oil collects at the bottom of the vessel. More oil may be obtained from green fruits, but these yield less juice and less citric acid, and are therefore not gathered. The limes are then placed in a hopper with a sliding bottom through which they are supplied to two revolving rollers of gun-metal fur nished with projecting spikes of different lengths. By these the fruit is torn to small pieces, which fall on a coarse copper sieve placed below. After passing through this strainer the juice is run directly into oaken puncheons or casks containing 100 gallons. These casks are filled quite full so as to exclude air, and bunged down immediately, the small proportion of essential oil contained in the vegetable matter which passes through the sieve helping to preserve the juice from decomposition. The slightly musty flavour of lime juice is produced by keeping, even after a few days, although the fresh juice is quite free from it. The whole of the limes collected in the morning must be pressed for lime juice the same day, as the juice rapidly loses citric acid when exposed to the air, even as much as 3 ounces in one day, or the whole of the acid in three weeks. Even when run at once into the casks, although it may contain 13 or 14 ounces or rarely 15 ounces of citric acid per gallon, it seldom contains more than 9 or 10 ounces on arrival in England. The mass of fruit pulp, &c., remaining on the sieves is put in bags of coir or cocoa-nut fibre, and a number of these placed one upon another, with strainers between, are then submitted to strong pressure in a screw press, to obtain more juice, the marc left after expression being returned to the plantation as manure. The unsound limes are treated in like manner and the juice boiled down in copper pans to a consistence of about 40 (Twaddle), a loss of citric acid taking place if the liquor be further concentrated. It then forms a black fluid of a consistence approaching that of treacle, and is exported in casks to England for the manufacture of citric acid. Turbines of sixteen horse-power are used as the motors for the machinery. Although the lime begins to bear in three or four years, until the trees are seven or eight years old the crops are very small. The trees require pruning and attention to keep them free from a species of mistletoe with red or yellow berries and a kind of dodder. They are usually manured with cotton seed cake. A fungus resembling black dust, and apparently the same as that which attacks the lemon trees in Europe, occasionally injures the plantations. For these reasons they are continually being extended. The young plants are grown from seeds picked out of the straining sieves, and are planted about 15 yards apart. In the plantations in the higher parts of the island the limes show a tendency to assume the form of a lemon and to become thicker skinned, while nearer the sea they are smaller, more globular, and thinner skinned. The young leaves of the lime are used for per fuming the water in finger-glasses, a few being placed in the water and bruised before use. In 1874 concentrated lime juice was exported from Montserrat to the value of 3390 ; and in 1878 Surinam exported 34,900 litres of lime juice. From Dominica 11,285 gallons, valued at 1825, were shipped in 1875. Other trees belonging to the same natural order to which the name of limes have been given are Citrus acida, and Atalantia monophylla, the wild lime of the Hindus. Nyssa candicans, the ogeechee lime of North America, and Tilia europaea, the common lime or linden tree, belong to other natural orders. See Pharmacographia, 2d ed., p. 114; Bentley and Trimen, Medicinal Plantt. 54 ; Risso and Poiteau, Histoire naturel/e des Grangers, 1873 ; Alfonso, Colti- razione degli Agrumi, 1875. (E. 51. H.) LEMOXNIER, PIERRE CHARLES (1715-1799), a dis tinguished astronomer, was born in Paris, November 23, 1715, where his father combined the practice of astronomy with the profession of philosophy. His first recorded observation was made before he was sixteen, and the presentation of an elaborate lunar map procured for him admission to the Academy, April 21, 1736, at the early age of twenty. He was chosen in the same year to accompany Maupertuis and Clairaut on their geodesical expedition to Lapland. In 1738, shortly after his return, he explained, in a memoir read before the Academy, the striking advantages of Flamsteed s mode of determining right ascensions. Indeed his persistent recommendation of English methods and instruments combined with tho labours of Lacaille to effect a revolution in French practical astronomy, and constituted the most eminent of his services to science. He corresponded with Bradley, was the first to represent the effects of nutation in the solar tables, and introduced, in 1741, the use of the transit-instrument at the Paris observatory. He visited England in 1748, and in company with the earl of Morton and Short the optician continued his journey to Scotland, where he observed the annular eclipse of July 25. The liberality of Louis XV., in whose favour he stood high, furnished him with the means of procuring the best instruments, many of them by English makers, and gave him the command of the royal printing estab lishment for the publication of his works. Amongst the fruits of his industry may be mentioned a laborious investigation of the disturbances of Jupiter by Saturn, the results of which were employed and confirmed by Euler in his prize essay of 1748; a series of lunar observations extending over fifty years ; some interesting researches in terrestrial magnetism and atmospheric electricity, in the latter of which he detected a regular diurnal period ; and the determination of the places of a great number of stars, including twelve separate observations of Uranus, between 1765 and its discovery as a planet. In his lectures at the College de France he first publicly expounded the analytical theory of gravitation, and his timely patronage secured the services of Lalande for astronomy. His temper was irritable, and his hasty utterances exposed him to retorts which he did not readily forgive. Against Lalande, his jealousy having been excited by his preference for Lacaille, he closed his doors &quot; during an entire revolution of the moon s nodes.&quot; His career was arrested by paralysis late in 1791, and a repetition of the stroke terminated his life. He died at Heril near Bayeux, May 31, 1799. By his marriage with Mademoiselle de Cussy, he left three daughters, one of whom became the wife of Lagrange. He was admitted in 1739 to the Royal Society, and was one of the one hundred and forty-four original members of the Institute. He wrote Histoire Celeste, 1741 ; Tliloric dcs Cometes, 1743, a translation, with additions, of Halley s Synopsis ; Institutions astronomiqucs, 1746, an improved translation of Keill s text-book ; Nourcuu Zodiaquc, 1755 ; Observations de la Lune, du Soldi, et dcs fitoilcs fixes, 1751-75 ; Lois du magnetismc, 1776-78, &c.