LEADER 



666 



LECTUAL 



L.-pipe Contraction. L. -poisoning, plumbism ; saturn- 

 ism ; painters' colic ; lead-palsy ; systemic poisoning. 

 It is due to the introduction of lead into the system. 

 The symptoms are disturbed nutrition, anemia, the 

 gingival line, lead-colic, constipation, pains in the 

 limbs, local muscular paralysis (wrist-drop) and wast- 

 ing, saturnine encephalopathy, etc. The treatment 

 consists in stopping ingress of lead to the system, its 

 elimination by iodid of potassium, aperients, particularly 

 the sulphates, etc. L., Sugar of. See Plumbi 

 acetas. L., Vinegar of, liquor plumbi subacetatis, 

 q.v. Also applied to alkaline solutions of basic lead 

 salts. L., White, basic lead carbonate(PbC0 3 ) 2 .Pb- 

 (OH). r L., Pattison's White, the oxychlorid of 

 lead ; it is used as a paint. 



Leader (le'-der) [ME., leder, a leader]. A sinew or 

 tendon ; a main artery ; a terminal shoot. 



Leaf (lef) [ME., leef, leaf; Mrroc, a scale]. In botany, 

 an expanded plant-organ, produced laterally from the 

 stem or branch, and, regarding only the way in which 

 it originates, applied arbitrarily to the carpels, stamens, 

 floral envelops, cotyledons, and ordinary leaves. See 

 Folia. L.-cup. See Bearsfoot. L. -green. See 

 Chlorophyl. 



Leaflet [lef '-let) [ME., leef, a leaf]. A small leaf, or 

 leaf-like organ or appendage. 



Lean (/en) [ME., lene, lean]. Scant of flesh; thin; 

 spare. Free from fat. L. -faced, having a thin face. 



Leanness (len'-nes) [ME. ,lene, lean]. A condition 

 of having less than the usual amount of fat or flesh. 

 It may be natural, or the result of disease. 



Leap (lep) [ME., lepen, to spring]. To bound; to 

 spring up. 



Leaping (lep'-ing) [ME., lepen, to spring]. Springing ; 

 jumping. L. Ague, a synonym of Dancing Mania. 



Leash (lesh) [ME., leesshe, a leash]. The network of 

 branches into which a nerve-trunk, or a vessel may be 

 divided. 



Leather (Zetk'-er) [ME., letker, leather]. A material 

 manufactured from hides or skins by the process of 

 tanning, which may be done by a number of methods. 

 The following are the main varieties of leathers so 

 produced : Sole- leather; this is the heaviest and firm- 

 est variety of leather produced. It is made from the 

 heaviest and thickest hides, and is valued for its fine 

 grain and toughness. It retains the whole thickness 

 of the hide. Upper and Harness Leathers : these are 

 made from lighter hides, and are tanned for strength 

 and flexibility rather than for weight. The black 

 color and finish are put on upper leather by coating it 

 with a mixture of lamp-black, linseed oil, and fish-oil, 

 to which tallow and wax and a little soap have been 

 added. Morocco Leather ; the true morocco leathers 

 are manufactured from goat-skins. A cheaper grade, 

 known as French morocco, is produced from sheep- 

 skins. Enamelled or Patent JLeathers ; these are leath- 

 ers finished with a water-proof and brightly varnished 

 surface, similar to lacquered wood-work. Thin and 

 split hide is used for these. Russia Leather is peculiar 

 in its characteristic odor and its ability to withstand 

 dampness, without any tendency to mold, both of 

 which qualities it owes to the currying with the empy- 

 reumatic oil of birch-bark. Chamois Leather is a soft 

 felt-like leather, originally prepared from the skin of 

 the chamois-goat, but now made from other goat-skins 

 and from the "flesh splits" of sheep-skins. Crown 

 Leather is a variety intermediate between oil -tanned 

 and tawed leather, being stronger than the first and 

 more water-resistant than the latter. The leather 

 readily becomes moldy, but seems to be strong and 

 specially adapted for belting. IVhite-tanned or 

 " Tawed" Leather ; skins to be tanned with the hair 



on, as sheep-skin rugs, etc., as well as light calf-kid 

 and glove-leather, are always alum-tanned. The glove- 

 leather thus obtained has softness and considerable 

 strength, but is not thoroughly water-resistant. Parch- 

 ment and Vellum ; the first of these is prepared from 

 the skins of sheep and goats, and the second from the 

 skins of calves. The skins are washed, limed, un- 

 haired, and fleshed, and then stretched thoroughly. 

 They are then again well-scraped and rubbed with 

 pumice-stone, and allowed to dry on a frame in the 

 shade, care being taken to avoid sunshine or frost. Very 

 fine vellums are prepared with the finest pumice-stone. 

 Degras, a valuable side-product of the leather indus- 

 try. It is essentially an emulsion of oxidized fish-oil, 

 produced by soluble albuminoids. It is used largely 

 for currying purposes. L. -brown. Same as Pheny- 

 lene-brown. L.-wood. See Dirca palustris. 



Leathery (leth'-er-e) [ME.,lether, leather]. Resem- 

 bling leather ; applied to thickened arteries, to various 

 tough tissues in the body, and to the liver, spleen, 

 or lungs. 



Leaven (lev'-n) \_levare, to raise]. A name given to 

 several species of ferments belonging to the class of 

 Saccharomyces, of which the culture known as " sour 

 dough " is a common example. 



Leban, Leben (leb'-an, leb'-en) [Ar. , leban\. A 

 variety of fermented milk of the Arabs. It is made 

 by adding some of the fermented milk of the previous 

 day to the fresh milk as soon as it is brought in from 

 the milking. It is a slightly acid fluid of the consist- 

 ence of cream, with small, flaky curds, and with the 

 taste of buttermilk. It is easily digested, and hence is 

 suitable for invalids. It corresponds to the ' 'Malzoon" 

 of the Turks. 



Leber's Disease. Congenital malformation of the 

 optic nerve, with atrophy. Hereditary optic atrophy. 

 See Diseases, Table of. 



Lecat's Gulf. The dilated bulbous portion of the urethra. 



Lecheguana (la-cha-gvvan'-ah) [Port.]. A kind of 

 poisonous honey collected in S. America from flo 

 of the genera Paullinia and Serjania. It produces 

 hilarity, followed by heavy narcotic slumber, and later 

 by melancholic depression. Unof. . 



Lechopyra {lek-op'-ir-ah) [Ae^w, a lying-in woman ; 

 nip, fire, fever]. Puerperal fever. 



Lecithigenous (les-ith-ij' -en-us) \\ekSoc, yolk ; 

 vdv, to beget]. Producing lecithin. 



Lecithin (les'-ith-in) [/fnitior, yolk of egg], C^H,,,- 

 NP0 9 . A complex nitrogenous fatty substance occur- 

 ring widely spread throughout the animal body. 1 

 is found in the blood, bile, and serous fluid-, as 

 as in the brain, nerves, yolk of egg, semen, pus, and 

 white blood-corpuscles. It is a colorless, slightly 

 crystalline substance, readily soluble in cold, and 

 much so in hot alcohol. It swells up in water, 

 throws out curling filamentous processes at the 

 time. It is easily decomposed. The lecithins, 

 class, form a group of substances the type of \vh 

 normal lecithin. 



Lecithoid (les f -ith-oid) \1eki6oc, yolk; diSoc, like]. 

 Resembling lecithin. 



Lecithophore (les'-ith-o-for) \_7\eki6oc, yolk ; 



bear]. A layer of cells in the ovum, constituting tin- 

 floor of the segmentation-cavity. 



Lecithus (les'-ith-us) [Xiicdfoc, yolk]. The eg 



Lecithymen (les-ith-V -men) ['/JkiOoc, yolk; bfiijv, mem 

 brane]. The vitelline membrane. 



Leclanche Cell. See Cell. 



Leco (le'-ho) \Xtik6, penis]. The penis. 



Lectual (lel-'-tu-al) [L., lectus, a bed]. Pertainii 

 a bed or couch. L. Disease, a disease that confines 

 one to bed. 



