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 variety are susceptible of decided improvement by early and persistent training of the individual. In cases of the other kind, however, which are generally hereditary, he believes that amelioration can be brought about, if at all, only by a course of education applied to successive generations. The author finds fault with the general neglect of the subject in our schools, and also with | the methods practiced in the few instances where such training has been attempted. In the Washington schools the practice is to use a chart on which the various colors are painted. These colors soon become so faded and dim as to no longer represent what was originally intended; and, even with this imperfect chart, no systematic instruction is given in the comparison of the colors. The first requisite, in Dr. Burnett's opinion, for succeessfullysuccessfully [sic] teaching color to children is, that the method shall be simple and easy. The study should also be made interesting, so that the children will pursue it more as a diversion than a task. Each child should be taught separately, but the instruction may be carried on in such a manner that the other children can participate. As the main object is to enable the child to discriminate between the various colors, the comparison of one color with another will be the principal part of the work. But the pupil should at the same time be taught the names of the colors and shades, so as to be able to convey the impressions he has received in definite language. To carry out these indications in a simple and effective way, there are required—first, a set of sample colors with which comparisons are to be made; and, second, a collection of colors from which the pupil may choose such as are to be compared with the sample. For the former. Dr. Burnett recommends the following: "Take a half-sheet of white perforated cardboard (42 x 26 cm.) with the largest size perforations, and work into it, with Berlin wool, bars 18 cm. in length and 35 mm. in width, of each of the following colors: red, green, and blue, with a distance of 1·5 cm. between them. These should be as pure as possible, and represent the three primary colors. Then, beginning 3 cm. below, work in at the same distances apart each of the following colors of medium shade and as pure as can be got: purple, orange, yellow, pink, brown, and gray. A single skein of Berlin wool is generally enough to work a bar of the required length and width, which is sufficiently large to be seen distinctly across any ordinary schoolroom by a normal eye. This card is to be placed on a white background on the wall in sight of all the pupils." In the process of instruction the pupils are first familiarized with this card, and with the names of the colors represented on it, and, when able to designate each of these correctly, the teacher will explain what is meant by a "shade," and, taking a package of Berlin wools containing all the shades of the nine colors on the card, will pick out and exhibit to the class all the shades of one of the colors. After this, the shades are thoroughly mixed with the other colors in the pile, and the pupils are then called upon to do the choosing, arranging them in regular order from darkest to lightest. The same process is to be repeated with each of the colors on the card.

Population of Africa.—Accurate statistics of the population of Africa, and especially of the interior portions of the continent, are of course not yet obtainable, and it will probably be many years before several of the populous districts now known will be sufficiently accessible for a thorough census; but much important information has been gathered about the distribution of the inhabitants and the density of the population in the different parts of the country. In the region of the great lakes, for example, there are countries as thickly peopled as many of the states of Europe—relatively small areas which, according to Stanley, possess millions of inhabitants. Behna states that the negro regions are by far the most populous, while the desert parts represent the other extreme. M. A. Rabaud, in a paper published in the "Bulletin of the Marseilles Geographical Society," gives the following as the population of the different subdivisions of the continent: In the Soudan, the population is estimated at 80,000,000, or about fifty-three per square mile; the town of Bida, on the Niger, contains 80,000 inhabitants. The population of East Africa is estimated at 30,000,000, and that of Equatorial Africa at about 40,000,000. One of the latest authorities divides