of a biting taste, and a linseed-like smell. The oil belongs to the linoleic or drying series, having as its principal constituent linolein; and it possesses greater drying power than raw linseed oil. Its specific gravity at 15° C. is 0.925. Poppy oil is a valuable and much used medium for artistic oil painting. The fine qualities are largely used in the north of France (huile d' œillette) and in Germany as a salad oil, and are less liable than olive oil to rancidity. The absence of taste and characteristic smell in poppy oil also leads to its being much used for adulterating olive oil. The inferior qualities are principally consumed in soap making and varnish-making, and for burning in lamps. The oil is very extensively used in the valley of the Ganges and other opium regions for food and domestic purposes. By native methods in India about 30% of oil is extracted, and the remaining oleaginous cake is used as food by the poor. Ordinary poppy-oil cake is a valuable feeding material, rich in nitrogenous constituents, with an ash showing an unusually large proportion of phosphoric acid. The seed of the yellow horned poppy, Glaucium luteum, yields from 30 to 35% of an oil having the same drying and other properties as poppy oil; and from the Mexican poppy, Argemone mexicana, is obtained a non-drying oil used as a lubricant and for burning.
POPULATION (Lat. populus, people; populare, to populate), a term used in two different significations, (1) for the total number of human beings existing within certain area at a given time, and (2) for the “ peopling ” of the area, or the influence of the various forces of which that number is the result. The population of a country, in the former sense of the word, is ascertained by means of a census (q.~v.), which periodically records the number of people found in it on a certain date. Where, as is generally the case, detail of sex, age, conjugal condition and birthplace is included in the return, the census results can be co-ordinated with those of the parallel registration of marriages, births, deaths and migration, thus formingfthe basis of what are summarily termed 'vital statistics, the source of our information regarding the nature and causes of the process of “peopling, ” i.e. the movement of the population between one census and another. Neither of these two operations has yet reached perfection, either in scope or accuracy, though the census, being the subject of special and concentrated effort, is generally found the superior in the latter respect, and is in many cases taken in countries where registration has not yet been introduced. The countries where neither is in force are still, unfortunately, very numerous.
The Population of the World, and its Geographical Distribution. -Man is the only animal which has proved able to pass from dependence upon its environment to a greater or less control over it. He alone. accordingly, has spread over every quarter of the globe. The area and population of the world, as a whole, have been the subject of many estimates in scientific works for the last three centuries and are still to a considerable extent matters of rough approximation. Every decade, however, brings a diminution of the field of conjecture, as some form of civilized administration is extended over the more backward tracts, and is followed, in due course, by a survey and a census. It is not necessary, therefore, to cite the estimates framed before 1882, when a carefully revised summary was published by Boehm and H. Wagner. -Since 'then the laborious
P. F. Levasseur and L. Bodio have
and nearly nine-tenths of Africa. In the same category must be placed a considerable proportion of central, southern and Polar America (see CENSUS). There is little of the world which is entirely uninhabited; still less permanently uninhabitable and unlikely to be required to support a population in the course of the expansion of the race beyond its present abodes. Probably the polar regions alone do not fall within the category of the potentially productive, as even sandy and alkaline desert is rendered habitable where irrigation can be introduced; and vast tracts of fertile soil adapted for immediate exploitation, especially in the temperate zones, both north and south, only remain unpeople because they are not yet wanted for colonization. The geographical distribution of the population of the world is therefore extremely irregular, and, omitting from consideration areas but recently colonized, the density is regulated by the means of subsistence within reach. “La population, ” says G. de Molinari, “ a tendance de se proportionner a son débouché.” These, in their turn, depend mainly upon the character of the people who inhabit the country. Even amongst savages there are few communities, and those but sparse, which subsist entirely upon what is directly provided by nature. As human intelligence and industry come into play the means of livelihood are proportionately extended; population multiplies, and with this multiplication production increases. Thus, the higher densities are found in the eastern hemisphere, within the zone in which arose the great civilizations of the world, or, roughly speaking, between north parallels 25 and 40 towards the east, and 25 and 55 in the west. Here large areas with a mean density of over 500 to the sq. m. may be found either supported by the food directly produced by themselves, as in the great agricultural plains of the middle kingdom of China and the Ganges valley and delta; or else, as in Western Europe, relying largely upon food from abroad, purchased by the products of manufacturing industry. In the one class the density is mainly rural, in the other it is chiefly due to the concentration of the population into large urban aggregates. It is chiefly from the populations of the south-west of Europe that the New World is being colonized; but the territories over which the settlers and their recruits from abroad are able to scatter are so extensive that even the lower densities of the Old World have not yet been attained, except in a few tracts along the eastern coasts of Australia and North America. Details of area and population are given under the headings of the respective countries, and the only general point in Connexion with the relation between these two facts which may be mentioned here is the need to bear in mind that the larger the territory the less likely is its mean density-figure to be typical or really representative. Even in the case of small and comparatively homogeneous countries such as Holland, Belgium or Saxony there is considerable deviation from the mean in the density of the respective component subdivisions, a difference which when extended over more numerous aggregates often renders the general mean misleading or of little value. Distribution of Population by Sex.~After geographical dispersion, the most general feature amongst the human race is its division by sex. The number of speculations as to the nature of this distinction has been, it is said, well-nigh doubled since Drelincourt, in the 18th century, brought together 262 “ groundless hypotheses, ” and propounded on his own part a theory been completed in the case of Europe TABLE I; g and America, and, for the rest of the population in Unascel-tained world, the figures annually brought up 5q~ m- in thousands. P0PUlaU0n Percentage of: to date in the g¢, ,¢, ,S, ,, a, ,> ¢ yea, Book Contment. thousands .- — Piflgfgg A P 1 2251; be tiki? “;..;'§ . ““;..'i53;.@'“iH?' “9°" ° ..122;.'2f. U.§ :.“.:s:§ ©... e I .
abstract at foot of page has been Europe 3,82S* 327,743 405,759 1061 2-5* 1-3 derived. Asia - ~ 15,773 795»59I 918.324 58 43-2 59'4 T ~ ° - Africa. . . 11,507 205,823 126,734 II 90'I 77'4 mea1;tiredplal1Iid.1pt:ii1eni1niCtS still un Ameflca - - I7»208* 100,415 1491944 9l 50'0* 9'1 erated (ln any Oceania 3448 4,232 5.881 I'7 5'4 I9'5 strict sense) in the Old World are the ' — Turkish Empire, Persia, Afghanistan, Total 51,764 1,433,804 I,606, § ft2 3I'7l 50'4* 4I'4 China and the Indo-Chinese peninsula
- Including Polar regions.
T Excluding Polar regions.