BECQUEREL

becquerel, the name of a french family, several members of which have been distinguished in chemical and physical research. antoine cesar becquerel (1788-1878), was born at chatillon sur loing on the 8th of march 1788. after passing through the ecole polytechnique he became _ingenieur-officier_ in 1808, and saw active service with the imperial troops in spain from 1810 to 1812, and again in france in 1814. he then resigned from the army and devoted the rest of his life to scientific investigation. his earliest work was mineralogical in character, but he soon turned his attention to the study of electricity and especially of electrochemistry. in 1837 he received the copley medal from the royal society "for his various memoirs on electricity, and particularly for those on the production of metallic sulphurets and sulphur by the long-continued action of electricity of very low tension," which it was hoped would lead to increased knowledge of the "recomposition of crystallized bodies, and the processes which may have been employed by nature in the production of such bodies in the mineral kingdom." in biological chemistry he worked at the problems of animal heat and at the phenomena accompanying the growth of plants, and he also devoted much time to meteorological questions and observations. he was a prolific writer, his books including _traite d'electricite et du magnetisme_ (1834-1840), _traite de physique dans ses rapports avec la chimie_ (1842), _elements de l'electro-chimie_ (1843), _traite complet du magnetisme_ (1845), _elements de physique terrestre et de meteorologie_ (1847), and _des climats et de l'influence qu'exercent les sols boises et deboises_ (1853). he died on the 18th of january 1878 in paris, where from 1837 he had been professor of physics at the musee d'histoire naturelle. his son, alexandre edmond becquerel (1820-1891), was born in paris on the 24th of march 1820, and was in turn his pupil, assistant and successor at the musee d'histoire naturelle; he was also appointed professor at the short-lived agronomic institute at versailles in 1849, and in 1853 received the chair of physics at the conservatoire des arts et metiers. edmond becquerel was associated with his father in much of his work, but he himself paid special attention to the study of light, investigating the photochemical effects and spectroscopic characters of solar radiation and the electric light, and the phenomena of phosphorescence, particularly as displayed by the sulphides and by compounds of uranium. it was in connexion with these latter inquiries that he devised his phosphoroscope, an apparatus which enabled the interval between exposure to the source of light and observation of the resulting effects to be varied at will and accurately measured. he published in 1867-1868 a treatise in two volumes on _la lumiere, ses causes et ses effets_. he also investigated the diamagnetic and paramagnetic properties of substances; and was keenly interested in the phenomena of electrochemical decomposition, accumulating much evidence in favour of faraday's law and proposing a modified statement of it which was intended to cover certain apparent exceptions. he died in paris on the 11th of may 1891. antoine henri becquerel (1852-1908), son of the last-named, who succeeded to his chair at the musee d'histoire naturelle in 1892, was born in paris on the 15th of december 1852, studied at the ecole polytechnique, where he was appointed a professor in 1895, and in 1875 entered the department _des ponts et chaussees_, of which in 1894 he became _ingenieur en chef_. he was distinguished as the discoverer of radioactivity, having found in 1896 that uranium at ordinary temperatures emits an invisible radiation which in many respects resembles rontgen rays, and can affect a photographic plate after passing through thin plates of metal. for his researches in this department he was in 1903 awarded a nobel prize jointly with pierre curie. he also engaged in work on magnetism, the polarization of light, phosphorescence and the absorption of light in crystals. he died at croisic in brittany on the 25th of august 1908. bed (a common teutonic word, cf. german _bett_, probably connected with the indo-european root _bhodh_, seen in the lat. _fodere_, to dig; so "a dug-out place" for safe resting, or in the same sense as a garden "bed"), a general term for a resting or sleeping place for men and animals, and in particular for the article of household furniture for that object, and so used by analogy in other senses, involving a supporting surface or layer. the accompaniments of a domestic bed (bedding, coverlets, &c.) have naturally varied considerably in different times, and its form and decoration and social associations have considerable historical interest. the egyptians had high bedsteads which were ascended by steps, with bolsters or pillows, and curtains to hang round. often there was a head-rest as well, semi-cylindrical and made of stone, wood or metal. assyrians, medes and persians had beds of a similar kind, and frequently decorated their furniture with inlays or _appliques_ of metal, mother-of-pearl and ivory. the oldest account of a bedstead is probably that of ulysses which homer describes him as making in his own house, but he also mentions the inlaying of the woodwork of beds with gold, silver and ivory. the greek bed had a wooden frame, with a board at the head and bands of hide laced across, upon which skins were placed. at a later period the bedstead was often veneered with expensive woods; sometimes it was of solid ivory veneered with tortoise-shell and with silver feet; often it was of bronze. the pillows and coverings also became more costly and beautiful; the most celebrated places for their manufacture were miletus, corinth and carthage. folding beds, too, appear in the vase paintings. the roman mattresses were stuffed with reeds, hay, wool or feathers; the last was used towards the end of the republic, when custom demanded luxury. small cushions were placed at the head and sometimes at the back. the bedsteads were high and could only be ascended by the help of steps. they were often arranged for two persons, and had a board or railing at the back as well as the raised portion at the head. the counterpanes were sometimes very costly, generally purple embroidered with figures in gold; and rich hangings fell to the ground masking the front. the bedsteads themselves were often of bronze inlaid with silver, and elagabalus, like some modern indian princes, had one of solid silver. in the walls of some of the houses at pompeii bed niches are found which were probably closed by curtains or sliding partitions. the marriage bed, _lectus genialis_, was much decorated, and was placed in the atrium opposite the door. a low pallet-bed used for sick persons was known as _scimpodium_. other forms of couch were called _lectus_, but were not beds in the modern sense of the word except the _lectus funebris_, on which the body of a dead person lay in state for seven days, clad in a toga and rich garments, and surrounded by flowers and foliage. this bed rested on ivory legs, over which purple blankets embroidered with gold were spread, and was placed in the atrium with the foot to the door and with a pan of incense by its side. the ancient germans lay on the floor on beds of leaves covered with skins, or in a kind of shallow chest filled with leaves and moss. in the early middle ages they laid carpets on the floor or on a bench against the wall, placed upon them mattresses stuffed with feathers, wool or hair, and used skins as a covering. they appear to have generally lain naked in bed, wrapping themselves in the large linen sheets which were stretched over the cushions. in the 13th century luxury increased, and bedsteads were made of wood much decorated with inlaid, carved and painted ornament. they also used folding beds, which served as couches by day and had cushions covered with silk laid upon leather. at night a linen sheet was spread and pillows placed, while silk-covered skins served as coverlets. curtains were hung from the ceiling or from an iron arm projecting from the wall. the carolingian mss. show metal bedsteads much higher at the head than at the feet, and this shape continued in use till the 13th century in france, many cushions being added to raise the body to a sloping position. in the 12th-century mss. the bedsteads appear much richer, with inlays, carving and painting, and with embroidered coverlets and mattresses in harmony. curtains were hung above the bed, and a small hanging lamp is often shown. in the 14th century the woodwork became of less importance, being generally entirely covered by hangings of rich materials. silk, velvet and even cloth of gold were much used. inventories from the beginning of the 14th century give details of these hangings lined with fur and richly embroidered. then it was that the tester bed made its first appearance, the tester being slung from the ceiling or fastened to the walls, a form which developed later into a room within a room, shut in by double curtains, sometimes even so as to exclude all draughts. the space between bed and wall was called the _ruelle_, and very intimate friends were received there. in the 15th century beds became very large, reaching to 7 or 8 ft. by 6 or 7 ft. viollet-le-duc says that the mattresses were filled with pea-shucks or straw--neither wool nor horsehair is mentioned--but feathers also were used. at this time great personages were in the habit of carrying most of their property about with them, including beds and bed-hangings, and for this reason the bedsteads were for the most part mere frameworks to be covered up; but about the beginning of the 16th century bedsteads were made lighter and more decorative, since the lords remained in the same place for longer periods. in the museum at nancy is a fine bedstead of this period which belonged to antoine de lorraine. it has a carved head and foot as well as the uprights which support the tester. another is in the musee cluny ascribed to pierre de gondi, very architectural in design, with a bracketed cornice, and turned and carved posts; at the head figures of warriors watch the sleeper. louis xiv. had an enormous number of sumptuous beds, as many as 413 being described in the inventories of his palaces. some of them had embroideries enriched with pearls, and figures on a silver or golden ground. the carving was the work of proux or caffieri, and the gilding by la baronniere. the great bed at versailles had crimson velvet curtains on which "the triumph of venus" was embroidered. so much gold was used that the velvet scarcely showed. under the influence of madame de maintenon "the sacrifice of abraham," which is now on the tester, replaced "the triumph of venus." in the 17th century, which has been called "the century of magnificent beds," the style _a la duchesse_, with tester and curtains only at the head, replaced the more enclosed beds in france, though they lasted much longer in england. in the 18th century feather pillows were first used as coverings in germany, which in the fashions of the bed and the curious etiquette connected with the bedchamber followed france for the most part. the beds were _a la duchesse_, but in france itself there was great variety both of name and shape--the _lit a alcove, lit d'ange_, which had no columns, but a suspended tester with curtains drawn back, _lit a l'anglaise_, which looked like a high sofa by day, _lit en baldaquin_, with the tester fixed against the wall, _lit a couronne_ with a tester shaped like a crown, a style which appeared under louis