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Cameron, Verney Lovett (1844 1894), Rosa Ursina, published in 1636. He demonstrates very African traveller, was born at Radipole, near Weymouth, clearly and practically the advantages and disadvantages 1st July 1844. He entered the navy in 1877, and was emof the different methods, without a lens, with a single convex lens, and with a telescope, as used in his helio- ployed for a considerable time in the suppression of the scope, which was a telephotographic arrangement on a East African slave-trade. The experience thus obtained led stand on Kepler’s principle. Here we first find the dark to his being selected to command an_ expedition sent out chamber constructed of wooden rods covered with cloth or by the Royal Geographical Society in 1873, to succour Dr Livingstone. Soon after the departure of the expedipaper, used separately to screen the observing tablet. Bettinus in his Apiavia (1645) has described several tion from Zanzibar, Livingstone’s servants were met the dead body of their master, but Cameron methods of measuring the sun and terrestrial objects by bearing continued his march, reached Ujiji, on Lake Tanganyika, the images projected through an aperture, and also methods February 1874, and, after solving the principal geofor erecting the inverted images formed by lenses in the in graphical problems connected with that lake, proceeded camera obscura. In 1646, Fr. Kircher published his well- south-west, continually making discoveries in regions never known Ars Magna Lucis et Umbrce, and in it ha,s gathered before visited by any European. His travels were pubmost of the information then available on the principle and lished, under the title Across Africa, in 1876. The use of the camera obscura and methods of optical projection. remainder of Cameron’s life was chiefly devoted to proIt is noticeable that he first uses the word conclave, a box jects for the commercial development of Africa, and to or cage, like Scheiner’s, as alternative to camera. The writing tales for the young. He also visited the Euphrates optical principles of the camera obscura with and without valley in connexion with the proposed railway, and accomlens were very fully treated by Schott in the first part of panied Sir Richard Burton in his West African exploration his Magia Universalis Naturae et Artis (1657), and he has in 1882. He wrote on both subjects. He was killed by discussed the nature and manner of production of the fall from horseback when returning from hunting, 24th image on the paper, the similarity of the eye to the camera, aMarch 1894. and the phenomena of vision. In his preface there is a useful list of early writers on optics. Cameroon, or Kamerun, in West Central Africa, It is difficult to ascertain when the camera first came to forms the north-west corner of the great Central African England The translation of Porta’s book, Natural Magick, plateau. This becomes evident in its eastern section, was published in 1658, and in the same year there is a where are wide-spreading plains, which farther west mention of a portable tent camera obscura for sketching, assume an undulating character, and gradually merge into in a work called Graphice, or the Most Excellent Art oj a picturesque mountain range. This range, running from Painting. In this the object glass of a “prospective north to south, is flanked by a second lower parallel range imace trunk,” or telescope, was used alone to throw the in the west, with a wide valley between. In the northimage on a sheet of paper on which the outline could be west the Upper Guinea mountains send their eastern spurs drawn. William Molyneux has given a number of optical just across the boundary, and from a volcanic rift, which problems relating to lenses in his Treatise of Dioptrics, runs south-west to north-east, the Cameroon peak rises to 1692. He states the relative proportions between the an elevation of 12,480 feet. Inland the Chebchi and diameters of the object and the image, and their distances Mandara mountains indicate the direction and extent o from the lens, and proves it geometrically by the case of the rift. Geologically, these three mountain groups belong the camera and lens. The analogy of the _ eye and the to so many different periods. The first is composed of camera is also discussed, as well as the optical theory of Archaic rocks, the part belonging to the Guinea mountains the dark chamber or camera with and without a lens. is of more recent ago, showing sandstones and clay schists, The first notice of a box, or portable camera with lens, while the rift mountains and Cameroon peak are purely appears to be in Zahn’s 0cuius Artificialis Teledioptmcus volcanic. The mountains of the plateau lose their meri(1702). He gives figures and descriptions of two forms : dional direction, sweeping grandly round to the east on one a wooden box with a projecting tube, in which two or reaching the eighth degree, of N. lat. Here they give three lenses could be fitted, the image from which was rise to a number of small rivers, which collect m the ri thrown on a screen of oiled paper and viewed through a and form the Benue, that passes between the two chief hole in the back of the camera about two or three inches groups of the rift mountains, and leaves the protectorate away. The second was fitted with a reflector to throw up to join the Niger. Cameroon is thus a mountainous the image on a horizontal screen on which it would be country, which has only, on the coast, a strip of low land. viewed unreversed. There is also a great deal of theoretical In the south, near Batango, this is very narrow; it widens and practical information on lenses in connexion with the towards the north. Here, at the foot of the peak, a camera and other optical instruments. From John Harris s number of estuaries cut deep bays which form excellent Lexicon Technicum (1704), we find that the camera obscura harbours. The small rivers which empty into them can fitted with the arrangement called the “ scioptric ball, and be ascended for some miles by steam-launches. The chie known as Scioptricks, was on sale in London, and after rivers of the protectorate are the Lom and Nyong, next to this must have been in common use, either as a sketching them the Lokunja and Kribi. The two former rise on instrument or as a show. Many patterns are described the central plateau, down which they leap m splendid in Joseph Harris’s Treatise on Optics, 1775, Huttons cascades; through the parallel coast range they break in Philosophical and Mathematical Dictionary, and other rapids, which indicate the extent of their navigability. books on Optics and Physics of that period. It is most probable that the Sannaga, an arm of the Lom, The camera obscura was first applied to photography by will also prove navigable for launches in its upper course J Wa Thomas Wedgwood about 1802. ( - -*) on the plateau. Through the Logone and Shan the Camerino, ^ town and archbishop’s see of Italy, country becomes tributary to Lake Chad, througi e Sanga to the Congo. . .. the Marches, province of Macerata, 24 miles S.W. from Climate.—Cameroon has a very considerable raintaii, Macerata, on an E. spur (1139 ft.) of the Apennines. It and though this is greater in a certain part of the year, is the seat of a “free” university, founded in 17W and there is hardly a month without rain. In the interior attended in 1898 by 234 students; 18 professors. Popu- four seasons can be distinguished; a comparatively dry lation, about 12,000.