A notice of fossil forms should not be concluded without the remark that indications of at least two species have been found in amber, a number disproportionately small if compared with other insects entombed therein; but it must be remembered that a dragon-fly is, as a rule, an insect of great power, and in all probability those then existing were able to extricate themselves if accidentally entangled in the resin.
See E. de Selys-Longchamps, Monographie des Libellulidées d’Europe (Brussels, 1840); Synopses des Agrionines, Caloptérygines, Gomphines, et Cordulines, with Supplements (Brussels, from 1853 to 1877); E. de Selys-Longchamps and H. A. L. Hagen, Revue des Odonates d’Europe (Brussels, 1850); Monographie des Caloptérygines et des Gomphines (Brussels, 1854 and 1858); Charpentier, Libellulinae europeae (Leipzig, 1840). For modern systematic work see various papers by R. M’Lachlan, P. P. Calvert, J. G. Needham, R. Martin, E. B. Williamson, F. Karsch, &c.; also H. Tumpel, Die Geradflugler Mitteleuropas (Eisenach, 1900); and W. F. Kirby, Catalogue of Neuroptera Odonata (London, 1890). For habits and details of transformation and larval life, see L. C. Miall, Natural History of Aquatic Insects (London, 1895); H. Dewitz, Zool. Anz. xiii. (1891); and J. G. Needham, Bull. New York Museum, lxviii. (1903). For geographical distribution, G. H. Carpenter, Sci. Proc. R. Dublin Soc. viii. (1897). For British species, W. J. Lucas, Handbook of British Dragonflies (London, 1899). For wings and mechanism of flight, R. von Lendenfeld, S.B. Akad. Wien, lxxxiii. (1881), and J. G. Needham, Proc. U.S. Nat. Mus. xxvi. (1903). For general morphology, R. Heymons, Abhandl. k. preuss. Akad. (1896), and Ann. Hofmus. Wein, xix. (1904).
(R. M‘L.; G. H. C.)
[1] A similar contrivance was suggested and (if the writer mistakes not) actually tried as a means of propelling steamships.
DRAGON’S BLOOD, a red-coloured resin obtained from several species of plants. Calamus draco (Willd.), one of the rotang or rattan palms, which produces much of the dragon’s blood of commerce, is a native of Further India and the Eastern Archipelago. The fruit is round, pointed, scaly, and the size of a large cherry, and when ripe is coated with the resinous exudation known as dragon’s blood. The finest dragon’s blood, called jernang or djernang in the East Indies, is obtained by beating or shaking the gathered fruits, sifting out impurities, and melting by exposure to the heat of the sun or by placing in boiling water; the resin thus purified is then usually moulded into sticks or quills, and after being wrapped in reeds or palm-leaves, is ready for market. An impurer and inferior kind, sold in lumps of considerable size, is extracted from the fruits by boiling. Dragon’s blood is dark red-brown, nearly opaque and brittle, contains small shell-like flakes, and gives when ground a fine red powder; it is soluble in alcohol, ether, and fixed and volatile oils. If heated it gives off benzoic acid. In Europe it was once valued as a medicine on account of its astringent properties, and is now used for colouring varnishes and lacquers; in China, where it is mostly consumed, it is employed to give a red facing to writing paper. The drop dragon’s blood of commerce, called cinnabar by Pliny (N.H. xxxiii. 39), and sangre de dragon by Barbosa was formerly and is still one of the products of Socotra, and is obtained from Dracaena cinnabari. The dragon’s blood of the Canary Islands is a resin procured from the surface of the leaves and from cracks in the trunk of Dracaena draco. The hardened juice of a euphorbiaceous tree, Croton draco, a resin resembling kino, is the sangre del drago or dragon’s blood of the Mexicans, used by them as a vulnerary and astringent.
DRAGOON (Fr. dragon, Ger. Dragoner), originally a mounted soldier trained to fight on foot only (see [Cavalry]). This mounted infantryman of the late 16th and 17th centuries, like his comrades of the infantry who were styled “pike” and “shot,” took his name from his weapon, a species of carbine or short musket called the “dragon.” Dragoons were organized not in squadrons but in companies, like the foot, and their officers and non-commissioned officers bore infantry titles. The invariable tendency of the old-fashioned dragoon, who was always at a disadvantage when engaged against true cavalry, was to improve his horsemanship and armament to the cavalry standard. Thus “dragoon” came to mean medium cavalry, and this significance the word has retained since the early wars of Frederick the Great, save for a few local and temporary returns to the original meaning. The phrases “to dragoon” and “dragonnade” bear witness to the mounted infantry period, this arm being the most efficient and economical form of cavalry for police work and guerrilla warfare. The “Dragonnades,” properly so called, were the operations of the troops (chiefly mounted) engaged in enforcing Louis XIV.’s decrees against Protestants after the revocation of the edict of Nantes. In the British service the dragoons (1st Royals, 2nd Scots Greys, 6th Inniskillings) are heavy cavalry, the Dragoon Guards (seven regiments) are medium, as are the dragoons of other countries. The light cavalry of the British army in the 18th and early 19th century was for the most part called light dragoons.