Page:Encyclopædia Britannica, Ninth Edition, v. 24.djvu/66

Rh V A M V A M cost, provided that it pays for these imports with exports which cost even less. A very striking example of this doctrine of comparative cost, as it is termed, is furnished by Victoria after the great gold discoveries. All kinds of produce were imported and paid for with gold, because there was less real cost involved in obtaining the gold to pay for imports than in making the articles. Accord ing to this theory every country will devote its labour and capital to its most productive uses ; and, if by some new imports a domestic industry is checked or abolished, it is argued that the labour and capital will be devoted to increasing the exports so as to pay for the new imports. It must clearly be assumed as axiomatic that in the absence of loans, tributes, &c., imports can in the long run only be paid for by exports, and also that those articles will be ex ported which can be produced at the least comparative real cost. This theory then may be held to explain in a satis factory manner the origin and development of international trade ; but the question of values is still undetermined. Recip- Consistently with exports paying for imports many differ- rocal de- en ^ ra t es of exchange are possible, and the particular rate u actually adopted is said to depend entirely on reciprocal demand. And in an extreme case, in which new countries trade solely in articles of which each has a monopoly, this answer would seem to be correct ; but, when we consider that under present conditions trading countries have many articles in common, and that a slight margin of profit suffices to expand or diminish an export trade, this answer seems too vague and unreal. The most probable solution seems to be that the rates of exchange will be so adjusted as to give to the exporters the ordinary rate of profits Foreign current in their respective countries. In general it is clear ex - that the rate will be determined independently of the changes. f ore ig n trade, or at least that the foreign trade is only one factor to be considered. It is said, for example, that the annual value of the agricultural produce of the United Kingdom exceeds the total amount of the exports. If the rate of profit falls, a trade which before was impossible becomes possible. The opinion may be hazarded that the best way of explaining the general theory of international values would be to start with the foreign exchanges ; but such an investigation is too technical and difficult for this place. (j. s. N.) VAMPIRE, a term, apparently of Servian origin (wampir), originally applied in eastern Europe to blood sucking ghosts, but in modern usage transferred to one or more species of blood-sucking bats inhabiting South America. In the first-mentioned meaning a vampire is usually supposed to be the soul of a dead man which quits the buried body by night to suck the blood of living persons. Hence, when the vampire s grave is opened, his corpse is found to be fresh and rosy from the blood which he has thus absorbed. To put a stop to his ravages, a stake is driven through the corpse, or the head cut off, or the heart torn out and the body burned, or boiling water and vinegar are poured on the grave. The persons who turn vampires are generally wizards, witches, suicides, and persons who have come to a violent end or have been cursed by then- parents or by the church. But any one may become a vampire if an animal (especially a cat) leaps over his corpse or a bird flies over it. Sometimes the vampire is thought to be the soul of a living man which leaves his body in sleep, to go in the form of a straw or fluff of down and suck the blood of other sleepers. The belief in vampires chiefly prevails in Slavonic lands, as in Russia (especially White Russia and the Ukraine), Poland, and Servia, and among the Czechs of Bohemia and the other Slavonic races of Austria. It became specially prevalent in Hungary be tween the years 1730 and 1735, whence all Europe was filled with reports of the exploits of vampires. Several treatises were written on the subject, among which may be mentioned Ranft s De Masticatione Mortuorum in Tumulis (1734) and Calmet s Dissertation on the Vampires of Hungary, translated into English in 1750. It is prob able that this superstition gained much ground from the reports of those who had examined the bodies of persons who had been buried alive though believed to be dead, and was based on the twisted position of the corpse, the marks of blood on the shroud and on the face and hands, results of the frenzied struggle in the coffin before life became extinct. The belief in vampirism has also taken root among the Albanians and modern Greeks, but here it may be due to Slavonic influence. Two species of blood -sucking bats (the only species known) Desmodus rufus and Dipliylla ecaudata repre senting two genera (see MAMMALIA, vol. xv. p. 415), inhabit the tropical and part of the subtropical regions of the New World, and are restricted to South and Central America. They appear to be confined chiefly to the forest- clad parts, and their attacks on men and other warm blooded animals were noticed by some of the earliest writers. Thus Peter Martyr (Anghiera), who wrote soon after the conquest of South America, says that in the Isthmus of Darien there were bats which sucked the blood of men and cattle when asleep to such a degree as to even kill them. Condamine, a writer of the 18th century, remarks that at Borja (Ecuador) and in other places they had entirely destroyed the cattle introduced by the mis sionaries. Sir Robert Schomburgk relates that at Wicki, on the river Berbice, no fowls could be kept on account of the ravages of these creatures, which attacked their combs, causing them to appear white from loss of blood. The present writer, when in South and Central America, had many accounts given him as to the attacks of the vam pires, and it was agreed upon by most of his informants that these bats when attacking horses showed a decided preference for those of a grey colour. It is interesting to speculate how far the vampire bats may have been instru mental when they were, perhaps, more abundant in causing the destruction of the horse, which had disappeared from America previous to the discovery of that continent. Although these bats were known thus early to Europeans, the species to which they belonged were not determined until about fifty years ago, several of the large frugivorous species having been wrongly set down as blood-suckers, and named accordingly. Thus the name Vampyrus was sug gested to Geoffroy and adopted by Spix, who also con sidered that the long-tongued bats of the group Glosso- phagx were addicted to blood, and accordingly described Glossopliaga soricina as a very cruel blood-sucker (sangui- suga crudelissima), believing that the long brush-tipped tongue was used to increase the flow of blood. Vampyrus spectrum, L., a large bat inhabiting Brazil, of sufficiently forbidding aspect, which was long considered by naturalists to be thoroughly sanguivorous in its habits, and named accordingly by Geoffroy, has been shown by the observa tions of modern travellers to be mainly frugivorous, and is considered by the inhabitants of the countries in which it is found to be perfectly harmless. Waterton believed Artibeus planirostris, a common bat in British Guiana, usually found in the roofs of houses, and now known to be frugivorous, to be the veritable vampire ; but neither he nor any of the naturalists that preceded him had suc ceeded in detecting any bat in the act of drawing blood. It fell to the lot of Charles Darwin to determine one of the blood-sucking species at least, and the following is his account of the circumstances under which the discovery of the sanguivorous habits of Desmodus rufus was made : &quot;The vampire bat is often the cause of much trouble by