Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/825

 G R A

G R A

Grass walks. Thefe are a great ornament in the Englifh gardens, our turf being, like our gravel, fuperior to that of any other country.

They are either made by turfing them with turf cut off from a common, or by fowing with hay feed, and will be always handfome with good rolling and frequent mowing. If the foil be dry, it is beft to lay thefe quite even, and level, but if damp, they may be laid a little rounding, but that not more than an inch in twenty feet. The oltener thefe walks are mowed and rolled in fummer, the thicker their bottoms will be, and in autumn they fhould be kept fhorter than at any other feafon, for if the blade runs up high at that feafon, the bottom will be bare in winter. All grafs walks ought alfo to be frequently polled, as the gardeners call it. This operation is the difperfmg the worm-cafts all over the walks with long afh poles ; this, befide deftroying the worm-caffs, is very beneficial to the graft of the walk. Miller's Gard. Dift. GRASSA, a name given by fome authors to native borax. GRASSETTE, in botany, the name given by the French to the pinguiada, or butter-wort, called alfo in YoxV&(\fefanicle. See Pinguicula. GRASSHOPPERS. Thefe animals are of the locuft kind, and fometimes come in fwarms to particular places, in the fame manner as that devouring creature does. They ap- peared fome years ago in Languedoc, and fome other places, in very formidable fwarms, and eat up all the harveft of feveral years. They took their flight like birds, and were about an inch long, and of a grey colour, in fhape wholly like the common gnaj "shoppers. They were found in many places covering the whole furface of the earth four or five inches deep, and ufed to lie quiet till toward noon ; but "when the fun then (hone warmly upon them they ufed to arife and take wing, and fettling on the corn-fields, they would in a few hours eat up the whole produce, ears, leaves, and even the more tender parts of the ffalks. When they had deftroyed one field in this manner, they ufed to take wing and fly to another. They ufually flew very high in the air, and directly againft the wind ; but as foon as they faw a new crop of con], they dropped together in a fwarm, and cleared it as they had done the firft. This practice they continued the whole day, and toward evenino- they fettled upon the ground, where they remained quiet till the heat of the following day raifed them again. When they had deftroyed all the corn in the country, they feized upon the vines, gatden herbs, and willows, and at laft upon the hemp, whole fields of which they eat up, notwithftand- ing its great bitternefs. Toward autumn they left off feed- ing, and were found in copulation, and foon after this the females were every where feen laying their eggs, which they depofited in the ground, making a hole with their tail large enough to receive a goofe quill. In thefe holes every female would lay forty or fifty eggs each of the fize of a millet feed, and when they had finifh- cd the laying, they covered up the hole to keep out the water ; after this they died apace, and the multitudes of their carcaffes flunk intolerably, poifoning the air. The next year they hatched in April, and from this one fwarm there were fuch prodigious numbers hatched, that fifteen tuns of them were deftroyed, while no bigger than flies, and nine tuns of their eggs before the hatching, and yet there remain- ed enough of them to deftroy, in a great meafure, the fuc- ceeding harveft. After this they gradually decreafed for fe- veral years, till they were not more numerous there than elfe- where. This was attributed to the induftry of the far- mers in killing them ; but it is more probable, that un- favourable feafons deftroyed them. Philof. Tranf. N° 182. p. 146. GRATINGS, in a fhip, are fmall ledges of fawed plank, framed one into another like a lattice, or prifon grate, ly- ing on the upper deck, between the main-maft and fore- jnaft, ferving for a defence in a clofe fight ; and alfo for the coolnefs, light, and conveniency of the fhip's com- pany. GRATIOLA, in botany, the name of a fmall plant not unfrequent in watery places. It is a fpecies of the dlntalis. See Digitalis.

Mr. Geoffroy has obferved, that the leaves of this plant are a very ftrong purge, and that in the dry extrafl, a method he is very fond of, for the extracting the virtues of many medicines. A brifk purge may be prepared from the gratiola, which operates in a fmall dofe, and without any difa<rreeabli tafte. The manner of preparing it is this. The leaves are to be infufed in water, till they have communicated their virtue to it by the means of heat, and this liquor is to be evapo- rated over a balneum maria; to a perfect drynefs ; when it leaves a dry pulverifable extract, that operates ii dofe of eight or ten grains. Mem. Acad, b'cienc. 17,8 p. 287. ' 3

This is a very rough purgative, it often operates by vomits as well as by ftool, and carries off a ereat quantity of water in dropfical cafes. It alfo deftroys worms, and opens ob- Amotions of the vifcera. Its operation, however, is fo vic-i

iUPPl. Vol. I.

• lent, as to be only fit for perfons of robuft conftitutions;. The gratiola is ufually given in decoction in water or ale, half an handful being a fufficient dofe for a very ftrono- man. Its operation is rendered more mild, by being boiled in milk* and the decoction drank. It purges very well in the form of glyfters, but care muft be taken not to give it when the bowels are in an inflamed ftate.

Externally, it is faid to be a vulnerary, a cataplafm of the bruifed herb being fometimes applied to wounds with fu'e- cefs. GRAVE, (Cycl.) in the Italian mufic, ferves to denote a flow motion, fomewhat fafter than adagio, and flower than largo. Brcfs, Muf. Diet, in voc. See Adagio, and Largo. GRAVEDO {Cycl.) — The figns of a gravedo are a dizzinefs and heavinefs of the head, attended with tenfive and pref- fing pains, which fometimes become violently pungent and as it were burning, a remarkable turgefcence of the veflels^ thirft, and a drynefs of the mouth, and unfound fleep; and finally the breaft is drawn into confent, and is afflicted with a tenfive and oppreflive pain.

The gravedo is a fpecies or rather fymptom of the head- ach, and confequently is removed by the fame means ufed againft it. See Head-ach. GRAVEL (Cycl.) — The gravel of England as much excells that of France, Holland, Flanders, &c. as the grafs does; This and grafs are the natural ornaments of a country feat; We have feveral forts of gravel in the different parts of England, but that which is common on black heath ii the moft valuable fort for garden walks, as it confifts of round, even, and beautiful pebbles, and when mixed with a ftiff loam binds well, and keeps in order the longeft of all kinds of gravel. Gravel walks. Thefe are defervedly efteemed a vaft advan- tage, which our gardens have over thofe of all other nations. The method of laying fuch walks is this. The bottom fhould be laid with lime rubbifh, or lame flint ftones, or any other hard matter, for eight or ten "inches thick, to keep weeds from growing through, and over this the gravel is to be laid about fix or eight inches thick : This fhould be laid rounding up in the middle, by which means the larger ftones will run off to the fides, and may be raked away, for the gravel fhould never be fcreened before it is ufed, that fpoiling it. It is a common miftake to lay thefe walks too round, which not only makes them the more uneafy to walk on, but takes off from their apparent breadth. One inch in five feet is a fufficient proportion for the rife in the middle ; fo that a walk of twenty feet wide fhould be four inches higher in the middle than at the edges, and fo in proportion. As foon as the gravel is laid it ffiould be raked ■ and the large ftones thrown back again ; then the whole fhould be rolled both lengthwife and crofswife, and the pcr- fon who draws the roller fhould wear fhoes with flat heels that he may make no holes, becaufe holes made in a new walk are not eafily remedied. The walks fhould always be rolled three or four times in very hard fhowers, after which they will bind more firmly than they could ever be made otherwife to do.

Gravel, with fome loam among it, binds much more firmly than the rawer kinds, and when gravel is naturally very harfh and fharp, it is very proper to add a mixture of loam to it. The beft gravel for walks is fuch as abounds with fmooth round pebbles, which being mixed with a little loam, binds fo firmly, as never to be injured after, either by wet or dry weather. Thefe are not fo liable to be turned up by the feet in walking, as the more irregular fhaped pebbles, and remain much more firmly in their places after rollina- Miller's Gard. Difl. B '

GRAVELY land. The farmers obferve, that gravely and fandy lands eafily admit of heat and moifture, but that they have lefs advantage from the laft than any other lands, becaufe they let it pafs too foon, if they have a loofe under ftratum ; or retain it too long, if they have a firm one, fuch as clay, or a cold folid ftone. ■ From thefe accidents it either parches, or chills too much ; but when gravely ground has a thin coat of good mould at top, and a bottom of loofe ftone, it will produce excellent crops of grafs, for it will receive heat and moifture enough ; and if at any time it parches up the roots, the leaft rain refrefhes it again, and the growth is quicker than before. Mortimer's Hufbandry. Tom. 1. p. 69. GRAVITAS, BafuTwc, in the antient mufic, was ufed to fig- nify a found produced by the remiffion, or falling of the voice. Gravitas differs from remiffion, as the effect from its ^caufe. Vid. Arijtexen, p. 10—13. Edit. Meibom. Gravitas is alfo ufed to denote the ftate of a woman going

with child. See Pregnancy. GRAVITATION [Cycl.) is fometimes diftinfruifhed from gravity. Thus Monfieur Maupertuis takes gravity for that force, whereby a body would fall to the earth, fuppofed at reft; and gravitation for the fame, but diminiflied by the centrifugal force. See Fig. of the Earth determ. p. ac6. of Mr. Murdoch's tranflation.

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