Page:Encyclopædia Britannica, Ninth Edition, v. 14.djvu/458

 438 LEMON near Naples, and in this case are allowed to remain on the trees until ripe. Candied lemon peel is usually made in England from a larger variety of the lemon cultivated in Sicily on higher ground than the common kind, from which it is distinguished by its thicker rind and larger size. This kind, known as the Spadaforese lemon, is also allowed to remain on the trees until ripe, and when gathered the fruit is cut in half longitudinally and pickled in brine, before being exported in casks. Before candying the lemons are soaked in fresh water to remove the salt. Citrons are also exported from Sicily in the same way, but these are about six times as expensive as lemons, and a comparatively small quantity is shipped. Besides those exported from Messina and Palermo, lemons are also imported into England to a less extent from the Riviera of Genoa, and from Malaga in Spain, the latter being the most esteemed. Of the numerous varieties the wax lemon, the imperial lemon, and the Gaeta lemon are considered to be the best. The Greek island of Andros is said to produce ten millions of lemons annually ; these are exported chiefly to Constantinople, the Black Sea, and the Danube, realizing an average price of XI to .1, 3s. per thousand. Until recently the United States have been large im porters of lemons, at good prices, from the Mediterranean. In 1878 Palermo exported 463,977 boxes of this fruit, at 6s. 6d. per box. Owing to increased facilities for transit, and the hazardous character of the trade, the lemons are now chiefly exported by the proprietors of small plantations, io, in their eagerness to dispose of their stock, glut the market at New York and Philadelphia, and sometimes find the speculation a ruinous one. For some years past lemons have been extensively cultivated in the south of California, and the new industry will probably affect the Mediterranean trade to a serious extent. In 1874 half a million Californian lemons were received in San Francisco. Since it was found that, with a little care in the selection of the soil, these trees could be grown throughout the State, they have been planted in immense numbers, and the produce of each tree has been found to bring from 30s. to 60s. It has been esti mated that in a few years the produce will be equal to the requirements of the Pacific States and Territories, and that ultimately the whole of the United States may be supplied with lemons from California. In east Florida also, where suitable land is obtainable at 15 to 20 dollars an acre, lemons, limes, citrons, and more especially oranges, are being raised in abundance. In New South Wales lemons are also grown, having been introduced into Sydney about the year 1790. Lemons of ordinary size contain about 2 ounces of juice, of specific gravity 1 039-1 046, yielding on an average 32 5 to 42 53 grains of citric acid per ounce. The amount of this acid, accopding to Stoddart, varies in different seasons, decreasing in lemons kept from February to July, at first slowly and afterwards rapidly, until at the end of that period it is all split up into glucose and carbonic acid, the specific gravity of the juice being in February 1 046, in May 1 Oil, and in July 1 027, while the fruit is hardly altered in appearance. Mr Geo. Mee, however, states that lemons may be kept for some months with scarcely perceptible deterioration by varnish ing them with an alcoholic solution of shellac the coating thus formed being easily removed when the fruit is required for household use by gently kneading it in the hands. Besides citric acid, lemon juice contains 3 to 4 per cent, of gum and sugar, albuminoid matters, and 2 28 percent, of inorganic salts. Cossa has determined that the ash of dried lemon juice contains 54 per cent, of potash, besides 15 per cent, of phosphoric acid. In the white portion of the peel (in common with other fruits of the genus) a bitter principle called hes}&amp;gt;eridine has been found. It is very slightly soluble in boiling water, but is soluble in dilute alcohol and in alkaline solutions, which it soon turns of a yellow or reddish colour. It is also darkened by tincture of perchloride of iron. Another substance named lemoning, crystallizing in lustrous plates, was discovered in 1879 by Palerno and Aglialoro in the seeds, in which it is present in very small quantity, 15,000 grains of the seed yielding only 80 grains of it. From hesperidine it differs in dissolving in potash without alteration. It melts at 275. Various modes of preserving lemon juice in small quantities for medicinal or domestic use have been suggested. Mr Judicis states that if allowed to deposit and then filtered through paper it keeps Avell. DrSymes recommends heating the juice to 150Fahr. , filling bottles with it at that temperature, and immediately closing them when perfectly full so as to keep out access of air. Another writer advises the addition of 10 per cent, of alcohol. Perhaps the most simple method is to keep it covered with a layer of olive or almond oil in a closed vessel furnished with a glass tap, by which the clear liquid may be drawn off as required. As a commercial article for use on shipboard as a preventive of scurvy, lemon juice is largely consumed. By the provisions of the Act of Parliament 30 & 31 Viet. c. 124, 4, every ship going to other countries where lemon or lime juice cannot be obtained is required to take sufficient to give 1 ounce to every member of the crew daily. Of this juice it requires about 13,000 lemons to yield 1 pipe (108 gallons). Sicilian juice in November yields about 9 ounces of crude citric acid per gallon, but only 6 ounces if the fruit is collected in April. The crude juice was formerly exported to England, and was often adulterated with sea-water, but is now almost entirely replaced by lime juice. It is said, however, to be still an article of considerable export from Turkey, where lemons are abundantly grown, to Odessa. But a concentrated lemon juice for the manufacture of citric acid is prepared in considerable quantities, chiefly at Messina and Palermo, by boiling down the crude juice in copper vessels over an open fire until its specific gravity is about 1 239, seven to ten pipes of raw making only one of concentrated lemon juice. Of this concentrated juice Messina exported in 1877 1,631,332 kilogrammes, valued at 2,446,996 lire, and in!878 Naples exported it to the value of 767. Lemon juice for this purpose is prepared also from the fruits of limes and Bergamot oranges. It is said to be sometimes adulter ated with sulphuric acid on arrival in England. Essence or Essential Oil of Lemon. The essential oil contained in the rind of the lemon also occurs in commerce as a distinct article. It is manufactured chiefly in Sicily, at Keggio in Calabria, and at Mentone and Nice in France. The small and irregularly shaped fruits are employed while still green, in which state the yield of oil is greater than when they are quite ripe. In Sicily and Calabria the oil is extracted in November and December, as follows. A workman cuts three longitudinal slices oft each lemon, leaving a three-cornered central core having a small portion of rind at the apex and base. These pieces are. then divided transversely and cast on one side, and the strips of peel are thrown in another place. Next day the pieces of peel are deprived of their oil by pressing four or five times successively the outer surface of the peel (zest or flavedo) bent into a convex shape, against a flat sponge held in the palm of the left hand and wrapped round the forefinger. The oil vesicles in the rind, which are ruptured more easily in the fresh fruit than in the state in which lemons are imported, yield up their oil to the sponge, which when saturated is squeezed into an earthen vessel furnished with a spout and capable of holding about three pints. After a time the oil separates from the watery liquid which accom panies it, and is then decanted. By this process four hundred fruits yield 9 to 14 ounces of essence. The prisms of pulp are afterwards expressed to obtain lemon juice, and then distilled to obtain the small quantity of volatile oil they contain. At Mentone and Nice a different process is adopted. The lemons are placed in an ecuelle a piqucr, a shallow basin of pewter about 8 inches in diameter, having a lip for pouring on one side and a closed tube at the bottom about 5 inches long and 1 inch in diameter. A number of stout brass pins stand up about half an inch from the bottom of the vessel. The workman rubs a lemon over these pins, which rupture the oil vesicles, and the oil collects in the tube, which when it becomes full is emptied into another vessel that it may separate from the aqueous liquid mixed with it. AVhen filtered it is known as Essence de Citron au Zcste, or, in the English market as perfumers essence of lemon, inferior qualities being distinguished as druggists essence of lemon. An additional product is obtained by immersing the scarified lemons in warm water and separating the oil which floats off. Essence de Citron distillec is obtained by rubbing the surface of fresh lemons (or of those which have been submitted to the action of the ecucllc a piqucr} on a coarse grater of tinned iron, and distilling the grated peel. The oil so obtained is colourless, and of inferior fragrance, and is sold at a lower price, while that obtained by the cold processes has a yellow colour and powerful odour. Essence of lemon is chiefly brought from Messina and Palermo packed in copper bottles holding 25 to 50 kilogrammes or more, and sometimes in tinned bottles of smaller size. It is said to be rarely found in a state of purity in commerce, almost all that comes into the market being diluted with the cheaper distilled oil. This fact may be considered as proved by the price at which the essence of lemon is sold in England, this being less than it costs the manu facturer to make it. When long kept the essence deposits a white