697 



METAMARGARIC ACID. 



METEMPSYCHOSIS. 



darker in colour, may be formed by dissolving moist, recently precipi- 

 tated peroxide of iron in a hot solution of bitartrate of potash. This 

 compound is also used in medicine. 



A Hugs of iron are numerous, but only two are important, namely, 

 those with tiu and with zinc. The former will be found described 

 under TIN (tin-plate) ; the latter is produced when sheets of iron, 

 cleaned as perfectly as if required for tin-plate, are dipped into a bath 

 of melted zinc, on the surface of which is a stratum of sal ammoniac. 

 The surface of the iron then becomes alloyed with zinc, and is thus 

 preserved from oxidation by the air when employed in exposed situa- 

 tions. Moreover articles made of galvanised iron, as this zinc plate is 

 commonly called, are easily soldered together, which is not the case 

 with sheet-iron alone. 



.' fur iron. Solutions of the protoiall yield greenish or bluish- 

 white precipitates with the alkalies, or their carbonates; none with 

 sulphuretted hydrogen; black with sulphide of ammonium ; dark blue 

 with red prussiate of potash ; and light blue with the yellow prussiate 

 of potash. 



Solutions of the pertalts give red-brown precipitates with the alkalies 

 or their carbonates ; are reduced to the state of protosalts by sulphu- 

 retted hydrogen, a light yellow precipitate of sulphur occurring at the 

 same time ; are precipitated black by sulphide of ammonium ; dark 

 blue by the yellow prussiate of potash, and not at all by the red prus- 

 siate of potash. Exceedingly small quantities of iron may also be 

 detected in solution by the sulphocyanide of potassium, which gives a 

 red liquid, and by tmcture of gafls which produces a black colour 

 (ink). 



In the quantitative egtimation, of iron the metal is always weighed in 

 the form of peroxide. The definite state of the latter is ensured first 

 by boiling the solution with nitric acid in order that the iron may be 

 completely peroxidised, and second by precipitating with ammonia, 

 because any trace of the salts of that alkali may be readily expelled by 

 igniting the well washed precipitate. The resulting red oxide of iron 

 is pure sesquioxide (Fe, O 3 ), and contains, in one hundred parts, 

 seventy of iron (Fe) and thirty of oxygen (0). 



Ferrwyanoyen ( Fey or Cf y = FeCy 3 ) is a bibasic radical which has 

 not been isolated, but which is assumed to exist in certain familiar 

 chemical compounds. With two equivalents of hydrogen it forms 

 FERKOCYAMC ACID (H, Cfy), and with two of metal a class of salts 

 called ffrrocyanidei, of which ferrocyauide of potassium (Iv, Cfy) is a 

 type. 



ferridcycmugen (Fcdy or Cf dy = Fe, Cy ) is a similar radical, but 

 tribasic. With three equivalents of hydrogen it forms FERHIDCVAMC 

 ACID (H 3 Fcdy), and with three of metal, a class of salts called ferrid- 

 cyaiiidei, of which ferridcyanide of potassium (K, Fcdy) is the type. 



Prustian blue is a variable mixture of the f erro- and ferrid-cyanldes of 

 iron. [BLUE : pruaian blue.} 



METASIAUGARIC ACID. An acid of the same composition as 

 margaric acid. Its existence has not been satisfactorily established. 

 [MAROARIC ACID.] 



METAMECONIC ACID. [MECONIC ACID.] 



METAMERIC COMPOUNDS. [ISOMERISM.] 



METAMERIDE3. Chemical compounds which have the same 

 combining proportion, but which differ in constitution and properties. 



M i: TAOLE1U ACID. [OLEIC ACID.] 



M KTA 1'rXTIC ACID. [PECTlc ACID.] 



METAPHOR (lUTtvpofxi, literally 'a transference'), a figure of speech 

 which renders the subject of discourse striking, by the aid of expres- 

 sions primarily referring to other objects. A common kind of 

 metaphor is that called personification, where inanimate beings are 

 represented as endowed with life, and even with feeling, reason, &c., 

 as " the fields do laugh and sing," " stern winter." If this kind of 

 metaphor spiritualises the corporeal, another kind, on the contrary, 

 embodies the spiritual, as " the star of renown" " the pinnacle of 

 honour," and so on. A third kind is little else than a shortened 

 gimile, two objects in the same sphere being brought together, only on 

 ut of their resemblance. To this kind belong such expressions 

 as ' the silver moon" " the golden sun," &c., where it will be seen 

 ut once that " silver" and " moon," gold" and " sun," are connected 

 un.'ivly on account of their obvious similarity of colour aud bright- 

 ness. The origin of the first two kinds of metaphor is not so appa- 

 rent, for though they likewise express a similarity, yet the similarity of 

 a series of bodily objects to a series of objects merely of the mind, 

 where there can of necessity be no sensible resemblance, is a subject 

 for psychological investigation. The application of certain metaphors, 

 in all languages aud among all people, attracted the attention of Jean 

 Itichter, who remarked that, " no nation called error, light, or 

 truth, darkness." If we attend to the state of language, we shall lind 

 that a great part of the commonest discourse is composed of metaphors 

 of tliu second kind, and that nearly all words expressing mental 

 states, operations, and affections are in fact metaphorical. Thiu, \v>: 

 My every day " a man of extended views'' " a man o good capacity, 

 acute judgment," &c., where the words " extended," " views," " capa- 

 city," " acute," evidently belonged originally to material objects, but 

 have been applied to li < .turial by metaphors. The circum- 



Itance that material object* are more apparent, that language aecms 

 primarily tn hurtlum t. , , cts, and that when a higher 



degree of > '.>itli it objects belonging to the mind 



alone, nothing is left but to apply in a new sense the words already 

 formed, is sufficient to explain the use of these metaphors generally. 

 But still the fact that such aud such bodily attributes are univer- 

 sally predicated of such and such spiritual objects alone, may still 

 furnish matter for consideration to the curious in psychological 

 speculation. 



METAPHYSICS, a name originally applied to those books of Aris- 

 totle which followed his ' Physics/ and which his editors called ' the 

 books after the Physics' (jueri TO </>u<ra). In modern times the word 

 has been variously applied, and seems to assume quite a distinct mean- 

 ing as employed by dill'erent authors. With the Germans, metaphy- 

 sics is a science purely speculative, which soars beyond the bounds of 

 experience. The objects of this science are supersensual ideas, unat- 

 tainable by experience, and the difficulty of denning the word lies in 

 the circumstance that the very knowledge of the ideas sought requires 

 some proficiency in the study. Hence to one altogether unacquainted 

 with speculative philosophy it is almost impossible to explain the 

 meaning of the word " metaphysics" as used in this sense. The very 

 possibility of a science beyond experience has been denied by a great 

 number of philosophers, and many works called metaphysical should 

 rather be termed inquiries into the possibility of metaphysics. Thus 

 Kant's celebrated work, the ' Kritik der reinen Vernunft,' is a mere 

 inquiry into the possibility of a theoretical science of things beyond 

 experience, which terminates with a denial of such possibility ; and 

 hence some modern philosophers have considered Kant as no metaphy- 

 sician, but as a critic of the mental faculties, whose labours were to ba 

 the precursors of a new system of speculation. On the other hand, a 

 work like Spinoza's " Ethics'' is purely metaphysical. He assumes the 

 possibility of his science, and, proceeding from a number of axioms, 

 speculates accordingly. Those who deny the possibility of metaphysics 

 deny even the right to assume any axioms as applicable to a sphere 

 beyond experience ; and those who did assume them, as Spinoza, 

 Liebnitz, and Wolf, were called by the Kantians dogmatists, in opposi- 

 tion to their own appellation of critics. The great point to be established 

 prior to metaphysical speculation is the identity, or at least the 

 necessary concurrence, of thought and being. This once established, 

 speculative inquiry may proceed, as the results of logical investigation 

 must in such a case, of course, concur with the nature of being itself ; 

 but the sceptics always deny the right of assuming such identity or 

 concurrence, while on the other hand th'8'erent theories have been 

 adopted to prove them, such as those of harmony between body and 

 spirit, of the non-being of body altogether, except as an affection of 

 spirit, of an absolute identity between thought and being, &c. It 

 may be as well to observe that the critical philosophy, which assumes 

 nothing but the " I" or " ego," and the laws of thought (Fichte deduc- 

 ing" even the latter from the axiom, " I am I"), has Descartes for its 

 author, whose " Cogito, ergo sum," lies at the basis of most modern 

 systems. [DESCARTES, in Bioo. Div.] 



In England, the word metaphysics is usually applied to denote the 

 philosophy of mind, as distinguished from that of matter. This 

 science treats of the association of ideas, memory, and various pheno- 

 mena of mind ; and as it consists merely in collecting facts and 

 making inductions like any other experimental science, its possibility 

 is no more questionable than that of chemistry or electricity. How- 

 ever, Locke's ' Essay on the Human Understanding," as a denial of any 

 source of knowledge other than experience, may be put at the side of 

 Kant's ' Kritik,' as containing inquiries of similar nature, though the 

 results be different ; Berkeley's ' Idealism" may be compared with the 

 " Wissenschaftslehre' of Fichte, and the Common-sense theory of Reid 

 with the views of Jacobi. The philosophy of mind as an experimental 

 science has been chiefly treated by the modern Scotch philosophers, 

 among whom the late Sir W. Hamilton holds a high place. 



METATARTARIC ACID. [TAKTAUIC ACID.] 



METEMPSYCHOSIS (inTt^uxiaa^), derived from a Greek word 

 signifying the passage or transmigration of souls, forms a part of the 

 philosophical or religious belief of many nations. The Hindus believe 

 that the souls of men pass after death into different bodies, either of 

 men or animals, unless an individual has lived a most holy and religious 

 life; in which case his soul is absorbed into the divine essence. " The 

 soul passes from one state to another invested with a subtile frame 

 cun.sisting of elementary particles, the seed or rudiment of a grosser 

 body. Departing from that which it occupied, it ascends to the moon, 

 where, clothed with an aqueous form, it experiences the recompense of 

 its works ; and whence it returns to occupy a new body with resulting 

 influence of its former deeds. But he who has attained the true know- 

 ledge of God does not pass through the same stages of retreat, but 

 proceeds directly to reunion with the Supreme Being, with which he is 

 identified, as a river at its confluence with the sea merges thnvlu 

 altogether. His vital faculties and the elements of which his body 

 consists are absorbed completely and absolutely ; both name ami 1'nrui 

 cease ; and he becomes immortal without parts or members." 



(' Extracts from the HralM'i-ultras, or Aphorisms on the Vedanta 

 doctrine, by li.idariyana," translated by Mr. Colebrooke, in ' Trans, of 

 the Roy. As. Soc.,' vol. ii.) 



The migration of souls from one body to another also formei 1 

 well known, a leading feature of the Pythagorean doctrine. Tiiis 

 doctrine wai ;ils i a p:irt 01 the Egyptian religious syslrm. The 

 Iv-jypUaus, says Hurduti s (ii. Ui), are the first who believed iu the 



