Page:Popular Science Monthly Volume 5.djvu/776

756 treated. The use of the word insurance is all but universal among American insurance men; and the distinction made in the use of the term, in the foot-note to page five of the pamphlet, is merely one of Babbage's crotchets.

We agree with President Barnard in saying that the general circulation of Prof. Van Amringe's pamphlet will "do much to inspire confidence among the people in the wisdom and safety of this mode" (life insurance) "of providing against the uncertainties of the future."

is the first published installment of a series of maps and charts to comprise a "Statistical Atlas of the United States," designed to represent to the eye: 1. The physical features of the country; 2. The constituent elements and growth of population; 3. The vital statistics. The first and second parts will be published shortly. The third part, which is before us, comprises six maps and twelve charts. The maps, by variety of coloring, show the distribution of the statistical facts over the United States; while the charts, by a system of projected lines and shading, elaborate the details of the general idea, showing the facts as presented by States, sex, race, and age. For example: the first map shows the predomination of sex. Areas in which females predominate are left uncolored, while the remaining areas are colored deeply in proportion as the excess of males increases. The accompanying charts comprise a series of projections formed on the following principle; A vertical line, one inch long, is divided by horizontal lines into eight parts, representing as many decades. The angle to the left of the vertical line is supposed to represent males, and that to the right, females; and the shading of either angle indicates the predomination of the sex it stands for. Figures attached to the ends of the horizontal lines indicate by thousandths the number of individuals in each decade of life. The lowest horizontal line represents the first decade, and the length of each varies with the number of individuals in the decade it represents. In this way is shown the proportion between males and females in the aggregate population, the white, the colored, the foreign born, etc., in the United States as a whole, and in severalty. The birth-rate, and the death-rate from consumption, malarial diseases, intestinal diseases, and fevers other than malarial, are represented in like manner. The statistics of blindness, deaf-mutism, insanity, and idiocy, are shown in charts only. An explanatory text, to accompany the maps, will soon be issued.

little volumes aim at explanation of the technical terms used in building, and description of the parts they designate, entirely avoiding the larger subject of the principles upon which the art of building rests; or, more definitely, they explain what any part of a building is without telling how the building, as a whole, is constructed. The first takes up timber construction "as exemplified in the framing of floors, partitions, and roofs, explains the terms and describes the parts, and proceeds in the same manner with the subject as exemplified in doors, windows and internal fittings of houses," and with the lead and iron work connected therewith. The second similarly deals with the employment of brick, stone, slates, tile, etc., in building.

Each volume is accompanied by another volume of corresponding size, containing plates illustrative of the text.

aim of this book is the expression of primary principles, so as to be intelligible to beginners, while also serving as a text-book for more advanced students; and it answers this purpose very well. It begins by defining inorganic chemistry, enumerating the elements, stating the laws of affinity and combination and the principles of chemical nomenclature, and concludes with a description of the most important elements, and the combinations into which they enter.