Page:Popular Science Monthly Volume 52.djvu/871

Rh was published in 1731? A reference to Kolben's work would have given the student access to material which depicts the Hottentot before he had been seriously contaminated by contact with intrusive races, and would have explained the curious ceremonies connected with marriage and other rites and functions.

In regard to the dwarf tribes of Africa he says: "It is a pity that Stanley. . . has shown his usual tendency to exaggeration. With the dwarfs he has jumbled up children or misshapen beings such as negro chiefs keep at their courts for entertainment." Among the interesting generalizations is this one: "It has been correctly said that among negroes as elsewhere morality seems to stand in inverse ratio to the quantity of clothing, so that tribes that go naked are, so long as they remain untouched by foreign influence, the most chaste; those that are most clothed the least so." The missionaries can not or will not see the significance of this truth, and instantly demand a sudden change in habits engendered under a tropical sun, with the inevitable result of physical and moral degeneration of their converts.

His treatment of the African races is by far the most exhaustive, and the mass of new material in statement and in illustration will be of the greatest value to the American student.



important question of memory and its cultivation is the subject of the last volume in the International Scientific Series to reach us. What memory is, its place and importance in the economy of the human mind, its divisions and special functions, and, finally, methods for its cultivation, is the ground covered by Mr. Green's book. The great importance of a good memory is manifest; in fact, our intelligence depends almost entirely on the ability to remember what we learn, or, more accurately, what we perceive, as learning a thing implies the use of memory, so that any suggestions which may help to improve our ability to remember are worthy of close attention. Mr. Green says that in his own case, after a use of the methods he recommends, he found that he could learn a subject in about a fifth of the time that it previously took him. The special rules for memory cultivation occupy only the last fifty-five pages, although the whole subject is treated with special reference to this aspect of the question. The rules are simple, and, in fact, those which common sense would dictate—such as concentration of attention on the subject which it is desired to remember; the exclusion of unimportant and confusing details; frequent recalling of the impression; the use of as many faculties as possible in fixing the original impression; studying when the nervous force is abundant, etc.

When the political uncertainties of the scientific departments at Washington are considered, it seems really remarkable that anything at all is accomplished by them. For the successful prosecution of original research freedom from the petty cares of political maneuvering would seem essential, and yet some of these sections, notably the ethnological and geological, are constantly turning out valuable material. The last of their publications to reach us are a number of Geological Survey bulletins. The first one, No. 87, is by Charles Schuchert, and gives a synopsis of the American Fossil Brachiopoda, including a valuable bibliography and synonymy. The richness of North America in well-preserved Palæozoic brachiopods gives Mr. Schuchert's work a special interest. No. 127, by N. H. Darton, is a catalogue and index of contributions to American geology, and while there can be little said of it in the