Page:The New International Encyclopædia 1st ed. v. 06.djvu/554

DRY ROT. 483 DUALISM. rot continues to grow, weakening the timber. The timber may dry out without destroying the fungus, which recommences developing when moisture is ai;nin present. The use of some kinds of sound-deadening material, such as wet cement, coal-ashes, etc., is very favorable to the development of dry rot. Only dry gravel or coarse sand .sliould be used. Coal-cinders, etc., are alkaline, and the spores of Mcrulius lachry- nuins can be gcrniinatcd only in the proence of alkalies. Timber that is well seasoneil and pro- tected by ]>ainl will not be attacked by dry rot. A number of fungi attack the wood of trees, causing what is often called dry rot. Jlosl of these fungi belong to the class of toadstools and shelf fungi, and sometimes are seriously de- structive. This form of rot is caused on apple- trees by Polyporus hispidus; on oak, alder, poplar, " locust, and larch by Polyporus sul- phureus; on larch, Scotch and white ])ine, by Polyporus Schwiiiiitzii ; <m conifers by Fomes pinicola. etc. Diudalea cpiercina is a common saprophyte ui>on oak-stumps and oak-trees. The mycelium of this species forms leathery mats and is believed to be parasitic. The decompos- ing oak wood assumes a grayish brown color. DRY STOVE. Sec Ckekmioise. DRY TORTU'GAS. . group of ten islets belonging to -Monroe I'ounty, Klorida. and situ- ated at the extreme west end of the Klorida Iveys in latitude 24° ."i"' X. (Map: Florida. B 5). They are of coral formation, low, and are partially covered with mangrove bushes. Fort .Tefferson, on one of them, was a penal station during the Civil War. DUAL (Lat. thinlix). A technical term of grammar, used to denote that form of the noun, pronoun, adjective, or verb which refers exclu- sivcl.v to two persons or things. The dual num- ber dilTers. therefore, from the singular nunilier, which relates to one alone, and from the plural number, which relates indefinitely to many. The dual is regularly found in Sanskrit and in an- cient Greek : and in Latin it appears in the pronoun «»i6o (both), and in the numerals duo (two), octo (eight, i.e. two sets of four), and probably in viginii (twenty, i.e. two sets of ten). It is not generally found in the Teutonic lan- guages; yet the Oothic has it in the verb, and the Anglo-Saxon shows traces of it in two pro- nominal forms. It occurs in the Semitic lan- guages, e.g. the Arabic and the Hebrew, though in the latter only in the nouns. DUAL CONTROL. See Egypt. DU'ALINE (from dual, Lat. dualis, relating In lw<j I . A variety of dynamite invented by Ditt- mar. The absorbent, viz. cellulose derived from wood fibre, is nitrated and saturated with nitro- glycerin. The composition of dualine is said to be. nitroglycerin, HO parts; fine sawdust, 30 parts: nnd jiotassium nitrate. 20 parts. DUALISM (Lat. c/iia?is, relating to two). In philosopliy, the theory that the universe is ex- plicable only as a whole with two fundamentally ditrerent kinds of constituent elements. The nncicnt duali>im of matter and form has in mod- ern times been replaced by a dualism of mind and matter. .Vmons modern pliilosopliers Pes- cartes was the first to emphasize the radical differenie lictween thinking sMbstance (mindl and exteii'l- 'I -oli-tance (matter). Tbi. .liUNiili v suggested by this view was to explain how mind and matter interact as they apparently do in experience. Tiiis perplexity cau.sed some of his followers to deny interaction and assert con- comitance of variation (.see Ucc.vsio-Nalism) ; it caused others to deny the truth of dualism alto- gether (see ilo.MSM ; Sl'l.Noz.v; Leiuxitz). Since Dcscartes's day ihc cjucstion has been in con- stant debate, and even to-day there is no unanim- ity among philosophers as to the relative truth of dualism and its rivals. Within recent years the interest awakened by scientific psychology has brought the problem more to the fore, but even in psychology there is no consensus on the subject. (See P."r.li.elism.) Only a brief con- structive criticism can be undertaken here. The sole source from which a. satisfactory solution can be obtained is e.X|)cricnce. Does experience present us with one or two or even more ab- solutely dilVerent and fundamentally unrelated elements? In the first place, the contents of experience, the various sensations, centrally and peripherally aroused, the alTcctions and volitions, are, without _ question, qualitatively dillerent. These ditTerences may shade into each other (see CoxTiXLiTY, Law oi'), but no recognition of this fact can negative the fact of dilVerence. If monism (q.v.) denies the qualitative- difference, it is of course false. Some monism does this. But other forms of monism are more subtle. While admitting the existence of various dilTer- enees, they assert that these dilfcrcnces are va- rious manifestations of a simple substance. Their views stand or fall with the conception of substance (q.v.). But as the only tenable con- ception of substance seems to Ix- that it is a synthetic unity of various quantities, it would seem that while it is possible, and no doubl cor- rect, to think of the iniiverse as one connected system, or, in other words, a syntlu'lic unit, it is just as necessary to think of the differences within the unity. If monism be defined as the doctrine of the fundamental oneness of things, it is compatible with pluralism if that is de- fined as the doctrine of the fundamental plural- ity of things; since in a synthetic unity neither the unit}- is more fundamental than the differ- ences, nor the di(Veren<es than the unity. But is dualism compatible with monism and pluralism tlius harmonizecr; Evidcntl.v it is, if ])lur:ili-m n.cnns that all the dilVercnccs in the universe can be reduced to two classes, the psychical and the physical, however these may be dilfcrentiated from each other, and if it asserts that the differ- ences between these classes cannot be obliter- ated; for, as we see. tenable monism docs not deny differences, but asserts unity. Dualism is inconsistent with pluralism only if dualism denies the existence of more specific distinctions than those of psychical and physical. This dualism never ilocs. Dualism is inconsistent with monism only if it denies the possibility of recognizing the psychical and the physical as two aspects of one and the same experience. Dualism sometimes does this, and when it does it is false, for it overlooks the fact that the psychical and the phy-ic;«l are distinctions found correlated within the unity of experience. But dunlisni need not deny the correlation of |>hy«ic;il anil pMchical within a syntbetir unify, while yet insisllnL' ripon their irreducible differ- ences. Thus we find that moni-iii. dtiali<in. and pluralism are nin1i:illv iinnpatiblc, if the fact