268 ALDEN ALDERNEY calcium and further distilled until li part has passed over. It is further rectified by mixing 1 volume with 2 volumes of ether surround- ed by cold water, and passing ammonia through it to saturation. Crystals of aldehyde- ammonia separate, which are washed with absolute ether and dried; by subsequently distilling these crystals with sulphuric acid and a little water, pure anhydrous aldehyde is ob- tained. Aldehyde as commonly known is a thin, transparent liquid, with a strong, suffo- cating odor. It boils at 69 '5 F. It dissolves sulphur, iodine, and phosphorus ; absorbs dry sulphurous acid ; forms definite compounds with the acid sulphites of the alkali metals ; and reduces salts of silver. Upon this last property is founded the manufacture of silver mirrors by the reduction of nitrate of silver and the deposition of the metal upon glass. ALDEN, John, one of the first settlers of Ply- mouth, New England, was a magistrate in that colony for more than half a century, and died in 1687, aged about 89. On behalf of Miles Standish, Alden once proposed marriage to a pilgrim lady, who replied, "Prithee, John, why do you not speak for yourself? " The query led to John's becoming the lady's husband. This incident has been made the subject of a poem by Longfellow. ALDENHOVEN, a town in Rhenish Prussia, on the road from Jiilich to Aix-la-Chapelle ; pop. in 1867, 3,041. It is noted for a victory of the Austrians under the prince of Coburg over a part of the French army under Dumouriez, March 1, 1793, the result of which was the oc- cupation of Belgium by the allies. In October of the following year the vicinity of Alden- h oven again became the scene of considerable fighting between the Austrians and French, under Clairfait and Jourdan respectively, the result being in favor of the republican army. ALDER ( <>/// '/M, a genus of plants belonging to the natural order betulaceae. It has four stamens, and its fruit is without wings, by which characteristics it is distinguished from the birch, with which it was classed by the earlier botanists. The principal species are found in North America, though some of its varieties are met with on the eastern continent. The common alder (A. glutinosa) grows in moist localities, especially on the higher por- tions of swampy grounds, which are free from standing water. This tree is applied to many valuable purposes of practical utility. Its wood is prized by machinists as adapted to mill wheels and other work which is mostly under water. It is also in request for certain branches of cabinet-making and turnery. The charcoal made from its wood is of an excellent quality, and is highly esteemed for the manufacture of gunpowder. The bark, which contains an astringent juice, is used for tanning, and, with the addition of copperas and other ingredients, forms a dye for several colors. The alder is also an ornamental tree, with its abundant foliago of deep green. The Turkey alder (A. Alder Catkins and Seed. incana) is abundant in the north of Europe, and is found to the east, even beyond the Cau- casus. It is a taller and more erect tree than the common alder, and possesses many of the same properties, although it grows well in situations that are comparatively free from moisture. A beautiful species, A. cordifolia, or heart-leaved alder, is a native of Italy. The alder is easily cultivated, and, although not rapid in growth, can be obtained from seed with a great degree of certainty. ALDERMAN, a title derived from the Saxon ealdorman (elder man). The term ealdor was in itself a title of honor, used like the word " elder " in Scripture ; but the title ealdorman implied a higher degree of honor, and was among the Saxons applied generally to the chief dignitaries of state and the nobility, and specif- ically to certain national, county, and munici- pal officers, whose functions appear to have been chiefly judicial, but are not clearly defin- ed. In modern times the alderman is a legis- lative and judicial officer of municipal corpora- tions, elected or appointed according to the constitution or charter of the city in which he holds his office. ALDERNEY (Fr. Aurigny), the northernmost of the Channel islands, and the nearest to the French coast, separated from it by the race of Alderney (a strait which is very dangerous in stormy weather), about 7 m. W. of Cape La Hogue, the N. W. extremity of Normandy, and 24 m. W. N. W. of Cherbourg. It is about 4 m. long from N. E. to S. W. and 1 m. wide ; area, 1,962 acres; pop. in 1871, 2,718. There an picturesque cliffs on the S. E. coast, the high- est of which is 281 ft. There are several bays, but none safe and capacious enough for large vessels; and the English government has re- cently erected a granite breakwater off the harbor of St. Anne at a cost of 1,250,000, which, however, has not proved so useful as was anticipated. A series of forts was constructed around the island at the same time; also a
