AIKAID 



Alkaid, (al-kad'). [Ar.aZ, the; laid, mourner.] 

 =TJ Ursae Majoris: a star in the constellation 

 Ursa Major, at the end of the tail; also called 

 Beiietnasch. It derives its name from the 

 stars in the tail being supposed to be 

 mourners accompanying the bier formed by 

 the four stars of the bear's body. 



Alkali, (al'ka-li). [Ar. alkali, ashes of glass- 

 wort.]=Alkaline carbonate: also used gene- 

 rally for any substance, such as ammonia, 

 which counteracts an acid; also used for the 

 plant of glasswort. Fixed ^.=potash and 

 soda. Volatile -4.=ammonia. 



Alkali group of minerals. Sal-ammoniac, 

 kalinite, nitre, nitratite, halite: minerals 

 composed chiefly of ammonia, potash, or soda. 



Alkali metals. Caesium, lithium, potassium, 

 rubidium, sodium. Monad metallic ele- 

 ments having a great aflinity for oxygen, 

 BO that they all decompose water by simple 

 contact, and tarnish (or oxidise) in air; soft, 

 fusible, and strongly alkaline. 



Alkalimeter, (al-ka-lim'et-er). [Alkali, 3.7;.; 

 and Gk. metron, measure.] An instrument 

 to measure the amount of alkali present in 

 any substance. 



Alkaline, (al'ka-lin or alTca-lin). [Alkali, q.v.] 

 Having the properties of an alkali. 



Alkaline-earth group of minerals includes 

 barytes, calcite, gypsum, fludr, magnesite, 

 dolomite, &c., composed chiefly of baryta, 

 strontia, lime, or magnesia. 



Alkaline-earth metals Barium, Calcium, 

 strontium : dyad metallic elements which 

 decompose water by contact, whose oxides 

 combine very readily with water. 



Alkaloids, (al'ka-loidz). [Alkali, q.v.; and 

 Gr. eidos, form.]=Organic alkalies^vege- 

 table alkalies: compounds, usually found in 

 vegetables, resembling alkalis, and all con- 

 taining nitrogen; such as morphia, strych- 

 nia, &c. 



Alkanet, (alTca-net.) [Ar. al, the; kenna, 

 reed.]=Anchusa tiuctoria, the roots of wlxich 

 give a dark red dye. 



Allantoic acid, (al-lan-to'ik). [Allantois, q.v.] 

 =Amniotic acid: an acid obtained from the 

 fluid of the allantois. 



Allantoidea, (al-lan-toi'di-a), [Allantois, q.v. ; 

 and Gr. eidos, like. ] A division of Vertebrata, 

 including mammals, birds, and reptiles, all 

 of which have an amniou and an allantois^ 

 Abranchiate Vertebrata. 



Allantoin, ( al-lan-to'in ). [Allantois, q.v.]= 

 C 4 H 6 N 4 O 3 : a crystalline neutral substance 

 found in the allantoic fluid of the cow. 



Allantois, (al-lan-to'is). [Gr. Dallas, sausage; 

 eidos, form.] A membrane enveloping and 

 conveying nutriment to the foetus, in mam- 

 mals, birds, and reptiles. 



Allanturic acid, [Allantoin and Urea, q.v.]= 

 Glyoxalurea=C3H 4 N2O3: an acid obtained 

 from the decomposition, by heat, of allantoin. 



Allgood, (awl'good) = Chenopodium bonus- 

 henricus = Mercury: a common shrub be- 

 longing to Chenopodiacese. 



Allheal, (awl-hel)=Valeriana officinalis=Cat's 

 valerian : a meadow herb. The name is also 

 given to other plants. 



13 



AILYL 



Alliacese, (al-li-a'se-e). [Allium, q.v.] Some- 

 times used as a general term for lilies, &c. 



Alligator, (al-li-ga'tor). [Sp. al, the; lagarto, 

 lizard.] A large am- 

 phibious carnivorous 

 reptile covered with 

 horny scales, found in 

 rivers of N. America 

 Crocodilus lucius. 



Allioth=Alioth, q.v. 



Allituric acid, (al-li- 

 tu'rik). trfltoxa 

 and uric acid, q.v.]=" 

 C 6 H 6 N 4 p4, obtained 

 from uric acid and from alloxantin. 



Allium, (al'li-um). [L. allium, garlic.] 

 Strong flavoured herbs belonging to Lili- 

 acese, including garlic, wild leek, &c. 



Allman's classification of Polyzoa. Phylac- 

 tolaemata, with bilateral lophophore, and 

 epistome to mouth; Gymnolsemata, with 

 orbicular lophophore, and no epistome. 



AUochroite, (al-lok'ro-it). [Gk. allos, another; 

 chroa, complexion.] A variety of garnet, 

 marked by variety of colour in fusion. 



AUocotyledones = Allovitellians : Van Bene- 

 den's term for mollusca, worms, polyps, in- 

 fusoria, &c. 



Allophane, (al'lo-fan). [Gk. allos, another; 

 phaino, I appear.] A mineral of various 

 colours. 



Allophanicacid,(al-lo-fa'nik). [Allophane.g.v.] 

 Known only in combination=C2H 4 N 2 O 8 = 

 carbonate of urea and hydrogen =carbureic 

 acid. 



Allophanic ether = C 4 H 8 Xo0 3 : a crystalline 

 substance obtained from cyanic acid, and 

 from urea and oxalic ether. 



Allotropic, ( al-lo-trop'ik ). [Gk. allos, an- 

 other; trepo, I turn.] Having the capability 

 of assuming different conditions of molecular 

 arrangement; and of undergoing a change in 

 chemical and physical properties without 

 any change of chemical composition. 



Allotropism, (al-lot'ro-pizm). Capability of 

 assuming different states: change in mole- 

 cular arrangement. 



Alloxan, (al-lok'san). [From aHantoin and 

 oaralic acid.] Anhydrous ^4.=:mesoxal urea 

 =C 4 H2N2C>4 : a crystalline substance ob- 

 tained from uric and nitric acids. 



Alloxanio acid, ( al-lok-san'ik ). [Alloxan, 

 q.v.] = C 8 H 4 N 4 O 7 '3H 2 O : an unstable acid 

 obtained from alloxan. 



Alloxantin, (al-lok-san'tin). [Alloxan, q.v.] 

 =C 8 H 6 N 4 O 8 -2H 2 O: formed by the synthesis 

 of dialuric acid, alloxan, and water. 



Alloys, (al-loiz). [F. alloyer, to mix.] Mix- 

 tures of two or more metals: if one be mer- 

 cury =amalgam . 



All-seed, (awl'sed) Radiola, a small herb 

 belonging to Linacese. 



Allspice, (awl'spis). [Has the combined flavour 

 of clove, nutmeg, &c.]=Dried fruit of Eugenia 

 pimenta. 



Alluvium, (al-lu'vi-um). [L. alluvia, earth 

 deposited by water.] Loose gravel, sand, 

 &c., deposited on low land by water. 



Allyl, (al'lil). [Allium, q.v.] A hydrocarbon 



