MAGNESITE 



207 



MALACOLOGY 



Magnesite, (mag-ne'sit). [Magnesia, q.v.]= 

 Native carbonate of magnesia: an amorphous 

 mineral substance. 



Magnesium, (mag-ne'si-um). [Magnesia, q.v.] 

 =Mg": the type of the magnesian metals: a 

 white malleable metal, which burns with 

 dazzling brightness. 



Magnet, (mag'net). A piece of steel or soft 

 iron, which has the property of attracting 

 iron, probably by the polarization of its par- 

 ticles. Electro-M.: a piece of soft iron, mag- 

 netised by a current of electricity being sent 

 through a wire coiled round it. Natural 

 3f.=Loadstone. 



Magnetic, (mag-net'ik). [Magnet, q.v.] M. 

 pyrites: iron pyrites having magnetic pro- 

 perties. M. battery: a number of magnets 

 combined to act as one. M. elements: inten- 

 sity, declination, and dip, q.v. M. induction: 

 the magnetization of a piece of soft iron by 

 holding near it a strong magnet. M. elec- 

 tricity: electricity generated by the presence 

 of a magnet. M . poles of the earth : the two 

 points toward which magnets point when free 

 to move. In 1657 these coincided with the 

 geographical poles. M. fluid: the hypothe- 

 tical fluid supposed to be present in magne- 

 tised bodies. M. inclination=Dip: the angle 

 which a magnet makes with the horizon when 

 free to move in the vertical plane, coinciding 

 with the magnetic meridian. M. intensity: 

 the force with which a magnet is attracted 

 by the earth. M. declination=~M.. variation: 

 the angle between the lines pointing from a 

 given point to the geographical and magnetic 

 poles of the earth. M. oxide of iron=Black 

 oxide = Loadstone FesO^ M. equator=. 

 Aclinic line, q.v., on which dip=0. M. 

 meridian, v. Meridian. 



Magnetism, (mag'ne-tizm). [Magnet, q.v.} 

 The attraction of iron by magnets; a form 

 of insensible molecular motion: a variety of 

 energy known to us only by its attractive 

 or repellant power. Red M. ; attraction 

 by the N. pole of a magnet. Blue M.: 

 attraction by the S. pole of a magnet. Ter- 

 restial M.: the magnetic attraction of the 

 earth. 



Magnetisation, (mag-net-i-za'shun). [Magnet, 

 q.v.] The conferring upon a piece of iron or 

 gteel the properties of a magnet. M. of soft 

 iron by induction : either by placing near 

 it a magnet, or passing a galvanic current 

 through a wire twisted several times round 

 it. M. by the earth; a piece of soft iron left 

 for some time pointing to the magnetic pole 

 becomes feebly magnetised. 



Magnetite, ( mag'ne-tit ). [Magnet, q.v.]= 

 Native lodestone: the mineral which has 

 most magnetism: one of the iron group; 

 chiefly oxide of iron, crystallising in cubes, 

 and furnishing the finest quality of iron 

 when smelted. 



Magneto-electricity. Electricity derived from 

 magnetism. 



Magnetometer, (mag-net-om'e-ter). [Magnet 

 and Meter, q.v.] An apparatus for the de- 

 tection of magnetism, and for the measure- 

 Went of its intensity, 



Magnitude of stars 



6th mag. , just visible to the unassisted eye. 

 5th twice as bright , 



4th 

 3rd 

 2nd 

 1st 



6 times as bright 



12 times as bright > as the 6th. 

 25 times as bright 1 

 100 times as bright ; 



Magnol's arrangement of plants. The first 

 division into families: made in 1689. 



Magnolia, (mag-no'li-a). [M. Magnol.] A 

 plant the type of Magnoliaceaj. M. auri- 

 CMtato=Indian physic. M. cordata=TLea.rt- 

 leaved cucumber tree. M. glauct 

 M. M. grandiflora=L&\\YQ\ bay. 



Magnoliacese, (mag-no-li-ii'se-e). [Magnolia, 

 q.v.]= Magnol iads: shrubs and large trees, 

 with fragrant flowers, belonging to Rauales. 



Magpie, (mag'pi). [Mag. for Margaret; Pica, 

 <7 ; tt.]=Pica: a crow- 

 like bird which may , 



be taught to speak. 



Magyar, (mad'yar 



[The Hungaria 



yar). 

 an 



name.] A European 

 people=Hungarians. 



Mahonia, (ma-ho'ni-a). 

 [Mr. M'Mahon, of N. 

 America.] = Ash-bar- 

 berry = Berberis fas- 

 cicularis: a tree be- 

 longing to Berberidaceae. 



Mahogany, (ma-hog'a-ni). [The S. American 

 name.]=: Timber of Swietenia mahogoiii: a 

 large tree belonging to Cedrelacese, the wood 

 of which is very hard and handsome. 



Maia, (ma'ya). A crab-like animal, the type 

 of Maiidae; a family of Crustaceans. 



Maid, (mad). A fish, somewhat resembling 

 the skate, belonging to Raiidse. 



Maiden-hair, M. /ern=Adiantum: a plant 

 belonging to Filices. M. 0ratt=Briza media. 



Maize, (maz). [Mahiz, the Haytian name.]= 

 Indian Corn=Zea mays: a 

 very prolific grass-like plant; 

 the chief corn food of tropi- 

 cal America. 



Majolica, (ma-jol'i-ka). [Ma- 

 jorca.] A soft enamelled 

 variety of earthenware, first 

 made in Majorca. 



Makis, (ma'kis) = Fox-nosed 

 monkey: an animal belong- 

 ing to Lemuridee. 



Malachite, (mal'a-kit). [Gk. 

 malache, mallow.]=Hydra- 

 ted or green carbonate of 

 copper: a beautiful mineral of the copper 

 group, with oblique crystallization, much 

 used for ornament: named from resembling 

 the mallow in colour. Blue M. = Azurite. 

 Green M. =Malachite. Lime M.: a silky, 

 green, hydrated carbonate of copper alloyed 

 with iron and lime. 



Malacolite, (mal-ak'6-lit). [Gk. malakos, soft; 

 lithos, stone. ]=Sahlite, q.v.'. a variety of 

 pyroxene. 



Malacology, (mal-a-kol'6-ji). [Gk. malakos, 

 soft; logos, discourse.] The science of mol- 

 luscous pr gqft-bodied animals, v- Mollusca, 



