LAY 



LEA 



LAXATOR. Any muscle which 

 relaxes tlic tension of the part into 

 wiiich it is inserted. 



LAX, LAX US. UifTuse, loose. 



LAY, LEY, LEA. A term applied 

 to land in the state of grass or sward. 

 This kind of ground is frcciuenlly dis- 

 tinguished into such as has been long 

 in tiie stale of sward, and such as is 

 newly laid down to grass, or into old 

 and new lays. An old lay, fallowed 

 or turned under, yields an admirable 

 preparation for potatoes, corn, wheat, 

 and numerous other crops. The 

 proper method of managing a new 

 lay is of great importance to the 

 farmer, which Young thought should 

 be by keeping it perfectly free from 

 stock for the following autumn and 

 Avinter after being laid down, when, 

 in the spring, it will afford a growth 

 of young grass highly valuable for 

 s4ieep, with which it should only be 

 well stocked, and kept down tlien, 

 and during the following summer ; 

 nothing, in his opinion, being more 

 pernicious than mowing a new lay, 

 as directed by certain authors, if it 

 be intended for permanent meadow. 



LAYERING. Propagation by /(/y- 

 er5, which are short branches of plants, 

 trees, or shrubs. The layer is strip- 

 ped of its lower leaves, a slit made 

 imder one of the central buds, and 

 the branch twisted or the bark taken 

 partially ofi", and then bent and pinned 

 down in the soil by a wooden pin ; 

 the wounded portion is placed from 

 two to si.K inches under the soil, and 

 covered with fine mould and sand ; 

 the end of the branch is trimmed to 

 one or two eyes above the soil ; in a 

 few weeks it will have thrown out 

 roots, and maybe cut away and trans- 

 planted at a suitable time elsewhere, 

 being a new plant. It is a very safe 

 method of propagation, and in some 

 flower plants nearly the only one. It is 

 practised in the summer and autumn, 

 and on the year's shoots in many ca- 

 ses, but usually on two-year shoots. 

 Plants so situated as to render it im- 

 possible to bend their branches to 

 the ground, may nevertheless be lay- 

 ered by having shoots introduced into 

 a pot or box of soil elevated to them, 

 452 



and supported in a convenient posi- 

 tion. A piece of bass matting tied 

 around the limb near a crotch may 

 be made to sustain the soil. This is a 

 common practice among the Chinese, 

 \\ ho cause branches of trees to root 

 in this manner by partially ringing 

 them, and covering such parts with 

 a ball of clay, which is kept moist. 



L.AYERS OF ^\"00D. The cir- 

 cular rings of wood or bark produced 

 annually. The number of wood lay- 

 ers in a trunk gives us an idea of the 

 age of the tree. 



LEA. See Laij. 



LEAD. A soft, inelastic, and duc- 

 tile metal, fusing at 612^ Faiirenheit : 

 sp. gr., 11 44. Melted in open ves- 

 sels, it absorbs o.xygen, and becomes 

 converted into massicot, which, being 

 fused, is litharge, the protoxide of 

 lead. The equivalent of lead is 103 73, 

 symbol Pb [Plumbum). The metal, 

 in the form of sheet, is very use- 

 ful for covering buildings and form- 

 ing gutters. From its softness, it is 

 also adapted for pipes, whic;h are 

 quite flexible. Lead cisterns and 

 pipes are objectionable as reservoirs 

 for rain water. It is used as an al- 

 loy with other metals. Lead is read- 

 ily soluble in nitric acid, and slowly 

 in strong acetic and carbonic acids. 

 Its most important compounds are 

 the carbonale (white-lead) and ace- 

 tate (sugar of lead). 



LEAD, BLACK. Plumbago. A 

 native carburet of iron. 



LEAF. An expansion of cellular 

 tissue and vessels appended to the 

 stem at the nodes ; it receives ves- 

 sels from the new wood on the up- 

 per, and contributes them to the bark 

 from the under surface. Along the 

 upper channels the ascending sap 

 flows, and the elaborated juices leave 

 the leaf by the inferior system, de- 

 scending between the new wood and 

 bark, and organizing new wood for 

 the next year and roots. Leaves are 

 articulated, and fall off entire in ex- 

 ogenous plants, but are expansions 

 of the bark, and not articulated in 

 endogens ; hence, when they die, the 

 fragments remain, decaying in the air. 

 The figures of leaves are innumera- 



