PRESTWICH. 381 PRESUMPTION. PREST'WICH. A cottou-mauut'acturing town in Lancashire, England, i^o miles north-north- west of Manchester (Map: England, D 3). It is a favorite residential suburb of ^Manchester mer- chants. Population, in 1S91, 10,900; in 1901, 12,800. PRESTWICH, Joseph (1812-96). An Eng- lish geologist. He was born at Clapham, Lon- don, and was educated at University College, London. Though engaged as a wine merchant until his sixtieth year, he frequently contributed to the Transactions of the Geological Society, and in 187-1 was appointed professor of geology at Oxford ( 1874-88 ) . His reputation rests chief- ly on his classification of the Tertiary deposits of England, which he was the first to correlate with the strata of the Paris basin, and on hi^ promulgation of the theory of man's contempo- raneity with other Pleistocene mammals. Of his publications, the most important is his treatise on Geology (2 vols., 1886-88), which is consid- ered one of the best existing presentments of the principles of the science from the point of view of the anti-uniformitarian. Professor Prestwich was president of the Geological Society of Lon- don (1870-72); vice-president of the Royal So- ciety (1870-71); and president of the Interna- tional Geological Congress ( 1888 ) . Consult the Life and Letters of Sir Joseph Prestwich, by his widow (1899). PRESTWICHTA (Xeo-Lat.. named in honor of Prestwicli, an English geologist. A fossil crab found in the Carboniferous coal meas- ures of Xorth America and Europe, and prob- ably closely ancestral to the modern horse- shoe crab or Limulus. The chief interest of this fossil lies in its close resemblance to one of the larval stages of Limulus, in which respect it forms a link in the history or phylogeny of the latter peculiar organism. PRESUMPTION (Lat. prwsumptio, antici- pation, from prcEsumere, to presume, anticipate, take for granted, from prw, before -f- sumere, to take). In law, in its broadest sense, an infer- ence as to the existence of a fact not known or proved to exist, which inference arises from its logical connection or association with certain other facts which are known or proved. As thus defined, a presumption may be nothing more than a mere inference of fact such as a jury is re- quired to make in rendering a verdict. Thus, proof of the loss of a vessel in a storm with the other attendant circumstances may create a pre- sumption or inference of the fact of death of a passenger suificient to justify a jury in finding the death of the passenger as a matter of fact, un- less the 'presumptive' proof of the fact of death is rebutted or explained away by proof of other circumstances. In a narrower and more important sense the term signifies an inference of fact which is re- quired by some positive rule of law to be made from the proof or kno^^^l existence of certain other facts. Thus, the proof that one has not been seen or heard from by his friends or ac- quaintances for a considerable period, together with other circumstances, may or may not give rise to the presumption of his death: but if the absence is prolonged for a period of seven years, it is a positive rule of the common law that such absence, when unexplained, shall be deemed pre- sumptive evidence of death. It is evident that the effect of a presumption of this class is to give a weight or significance to facts actually proved in a given case not war- ranted by logic and not justifying in the absence of an express rule of law a fijiding by the court or jury of the existence of the fact presumed. Such presumptions are based upon considerations of convenience and serve a useful purpose ia aiding in the proof of facts which it might be impossible to establish by any inference logically llowing from facts actually proved. It is for this reason that presumptions of this class are sometimes called 'presumptions of law'; that is, presumptions required by the law, as distin- guished from mere logical inferences of fact. In strictness, however, such presumptions are true presumptions of fact. The effect of the presump- tion is prima facie to establish a fact, which, however, may be rebutted by the proof of other facts inconsistent with the fact presumed. There is still a third class of presumptions so called, which are not true presumptions at all, but legal fictions. They are in reality rules of substantive law, although stated as presump- tions of fact, and consequently they cannot be explained or rebutted. Thus the conclusive 'pre- sumption' that a child under the age of seven has not capacity to commit a crime, or that one is presumed to know the law or the contents of certain public records, is not a presumption, but a positive rule of law which cannot be contro- verted. Oftentimes such rules of law originated as presumptions of fact, as, for example, the rule that twenty years' use of a right or interest in real estate gives rise to the conclusive presump- tion that such use is by virtue of a lost grant and is therefore lawful. Originally the presumo- tion was a presumption of fact, which might be rebutted like any other true presumption, but with the sanction of a long line of judicial de- cisions the presiunption became adopted as a rule of substantive law, if there had been twenty 3'ears' user of the property which established the lawfulness of the use as a matter of law, and the question as to whether the use of property was by virtue of a lost grant ceased to be a jury question. The function of true presumption is primarily to aid a litigant in sustaining the burden of proof cast upon him by the pleadings in a case or by the rules of procedure. Some of the typical presumptions, in addition to those already mentioned, are: One charged with a crime is presumed to be innocent. Infants between the age of seven and twelve are presumed to be incapable of committing a crime. A state of facts proved to exist is presumed to con- tinue to exist. Letters having been proved to have been properly mailed are presumed to have been received. The imexplained failure of a party to a litigation to testify in his owti behalf gives rise to the presumption that his testimony would be unfavorable to his case. This rule, how- ever, has no application to one placed on trial upon a criminal charge, as the effect of such a presumption would be to deprive the accused of his legal right not to testify. There are many other presumptions of less frequent use which are foimded upon the same general principles. See Burden of Proof, under Evidence. Consvilt the authorities noted under EvinENCE; also Law- son. The Lain of Presumptire Evidence (2d ed.. San Francisco, 1899).