S H A 



S H A 



about two months. The fhad at its firfl appearance, erpe- 

 cially near Gloucefler, is edeemed a very delicate fifh, and 

 fells dearer than falmon. The London fi(hmongers diftin- 

 guifti it from that of the Thames, by the French name of 

 alofe. Whether they fpawn in the Severn or Wye is not 

 determined, as their fry has not yet been afcertained. The 

 old fifh come from the fea in full roe. The iifherraen erro- 

 neoufly imagine that the bleak, which appears in multitudes 

 near Gloucefter in July and Auguft, are the fry of the 

 (had. Many of thefe are taken i.i thofe months only, but 

 none of the emaciated (hads are ever caught in their return. 

 Tlie Thames (had does not frequent that river till the month 

 of July, and is elteemed a very infipid coarfe fifh. About 

 the fame time, the tiuaile, a variety of the Chad, makes its 

 appearance near Gloucelter, and is taken in great numbers 

 in the Severn, but held in as great difrepute as the (had of 

 the Thames. The true (had weighs fometimes eight pounds, 

 hut their general fize is from four to (ive. The twaite, on 

 the contrary, weighs from half a pound to two pounds, 

 which it never exceeds. The twaite differs from a fmall 

 (had only in having one or more round black fpots on 

 the fides ; if only one, it is always near the gill, but com- 

 monly there are three or four, placed one under the other. 

 Pennant. 



No (had is to be taken in the Thames or Medway, except 

 from May lo to June 30. 39 Geo. II. cap. 21. 



SHADDOCK, in Boiany. See Citrus. 



SHADE, in Agriculture, any fort of proteftion em- 

 ployed for preventing the heat, cold, and rain, from afFetl- 

 iiig and injuring any kind of Rock, whether of the nature 

 of building or plantation, of the woody kind, &c. See 

 ScRV^F.s-Plantation, and Shelter. 



Shade, in Gardening, any thing that intervenes to ob- 

 fcure or proteCl plants from the rays of the fun. It 

 is effefted in various ways by the gardener ; as by mats, 

 covers, &c. 



Shade, provincially a (hed for fuel, or houfe for (helter- 

 ing live-ftock, Sec. ; it alfo fignilies to fhed as grain, as ufed 

 in fome places. 



Sh.'^de Mountain, in Geography, a mountain of Pennfyl- 

 vania, N.E. of Lewidown. 



SHADENDORFF, a town of Auftria; 4 miles N.E. 

 of Brugg. 



SHADING of Plants, in Gardening, the art of pro- 

 tcfting plants of young and tender growths in feed-beds, 

 &c. from the fun. It is a neceilary work on many occafions, 

 in warm, dry, funny wreatlier in fpring and fummcr, &c. in 

 pricking out various forts of fmall young plants from feed- 

 beds, into nurfery-beds, pots, &c. as well as fmall cuttings, 

 flips, above-gro'.uid ofT-fets, pipings, &c. as likevvife occa- 

 fionally in tranfplanting any kind ot more advanced plants, 

 flowers, &c. into beds, or pots, in a hot, dry fcafon ; and 

 fometimes to feed-beds of particular forts of fmall or curi- 

 ous feeds, in hot (uiiny days ; alfo to plants in hot-beds, 

 under frames and glalks, both of young and more advanced 

 growths. It is the moll commodioudy and efledlually per- 

 formed by garden mats in a fort of awning over the beds, 

 to plants in the full ground, or to thofe in pots placed clofc 

 together, or fometimes to feed-beds, cither in that way, or 

 by being fprcad on the furface ; in the latter method, being 

 occalioiially watered over the mats: or lometimej, in hot 

 dry we?ther, by fome loofe draw htter (Ircvved over feed- 

 beds, which by fcreening the furface from the parching fun, 

 and prefcrviiig the moilliire in the earth, promotes a more 

 ^uick, regular, and free germination in the feed ; and when 

 the plants are come up, the covering is foon drawn off 

 Kglitly with a wooden or other rake. To plants under 



glafles in frames, &c. the occafional (hading is efFeAed 

 either by mats fpread thinly over the glades, or fometimes 

 by a little loofe, long litter, (haken lightly over them, juft 

 during the fiierce heat of the lun. In all cafes the (hade 

 diould not be m.ade too thick, fo as to darken the plants too 

 much. 



Alfo in the bufinefs of occafional (hading, it it in general 

 only to be continued in the warme/l time of funny days, ge- 

 nerally longer to plants, cuttings, &c. which have not (truck 

 root, than thofe that are in a growing date ; and iu common 

 with all plants in the full ground, or others defigned for 

 placing in the open air, where occafional (liading is necef- 

 (ary, it (hould be difcontinued on evenings, mornings, and 

 niglits, that they may enjoy the benefit of the full fre(h air 

 at thefe times ; as alio the tender forts, ftriking or advanc- 

 ing in growth under glades, having occafional (hading when 

 the fun is powerful, in the warmer part of the day, (hould 

 remain unihaded before and after that time, that they may 

 receive the neceffary beneficial induence of light and air in 

 a proper degree. But in plants, cuttings, (lips, &c. that 

 have had occafional (hading till they have ftruck good root, 

 and begin to advance a little in a renewed growth, the 

 (hading (hould be modly dilcontinued gradually, efpecially 

 for thofe in beds, pots, &c. in the open ground, or others 

 defigned for tranfplantation, or for placing in pots, in the 

 full air for the fummer, according to their kinds : but in 

 fome fmall tender plants of fieiider growth, the occafional 

 (hading mav probably be neced'ary in longer continuation, as 

 till they acquire more drength ; and to plants remaining all 

 fummer in hot-beds, or under frames and glades, the con- 

 tinuance of occafional moderate (hading in hot funny days 

 will be proper ; but in mod young plants, cuttings, &c. 

 pricked out or planted as above, and defigned for the full 

 ground or open air, not continued under glades, the having 

 the benefit of occafional (hade till well (truck is all they 

 require. 



The forts of plants which require this kind of manage- 

 ment are very numerous ; but it is condantly mentioned in 

 their culture where necedary. 



SH ADMAN, in Geography, a town of Grand Bucharia; 

 36 miles N.N.E. of Termed. 



SHADOW, Shade, in Optics, a certain fpace deprived 

 of light, or where the light is weakened by the interpofition 

 of fome opaque body before the luminary. 



The doftriiie of (hadovvs makes a confidcrable article in 

 optics, adronomy, and geography ; and is the general found- 

 ation of dialling. 



As nothing is feen but by light, a mere (hadow is invifi- 

 ble : when, therefore, wc fay, we lee a (hadow, we mean 

 partly, that we fee bodies placed in the (hadow, and illu- 

 minated by light refiefted from collateral bodies ; and 

 partly, that we fee the confines of the light. 



If the opaque body, that projedts the (hadow, be per- 

 pendicular to the horizon, and the plane it is projefted on 

 be horizontal, the fliadow is called a rigl>t (hadow. Such 

 are the (hadows of iikmi, trre<, buildings, mountains, &c. 

 If the opaque body be placed parallel to the horizon, the 

 diadow is called a verfed diadow ; as the arms of a man 

 Itrctched out, &c. 



SilADOWtiyVom opaque Bodies, I.aius of the Projellion of. 

 I. Every opaque body projects a (hadow in the fame direc- 

 tion with the rays o( light ; that is, towards the part oppo- 

 fite to the light. Hence, as cither the luminary or the body 

 changes place, the diadow likcwife changes its place. 



2. Every opaque body projects as many (hadows, as there 

 are luminaries to enlighten it. 



3. As the light of the luminary is more intcnfe, the (ha- 



dow 



