Page:Cyclopaedia, Chambers - Supplement, Volume 1.djvu/834

 GUM

GUN

-jKc account, contrived as an imitation of the afitient tra-

, dition of the wren's fighting the eagle.

GULASISI, in natural hiftory, a name given by the people of the Philippine iflands, to a very fmall and very beautiful fpecies of parrot.

GULBE in architecture, the fame as gorge. See the 'article Gorge, Cycl.

GULE of Augujf, the day of St. Peter ad vincula, which is celebrated on the firft of Augult.

It is called the guk of Augujl, from the Latin gula, a throat, for this reafon, that one Quirinus a tribune, having a daughter that had a difeafe in her throat, went to pope Alexander, thefixth from St. Peter, and defired of him to fee the chains that St. Peter was chained with under Nero, which requeft being granted, and file, kifling the chains, was cured of her difeafe : whereupon the pope infti- tuted this feaft in honour of St. Peter; and, as before, this day was termed only the calends of Augulr, it was on this occafion called indifferently either the day of St. Peter ad-vincula, from what wrought the miracle, or the guh of Augujl, from that part of the virgin whereon it was wrought. Durand. Rationale Divinorum. lib. 7. c. 19.

. Terms of law.

GULL, fr zoology, properly the common name of all the

Lvrus kind, but generally underftood only as the name of

the common black and white kind. This is the largeft of all

1 the gull kind j it ufually weighs between four and five

, pounds. Its beak is yellow, flatted fideways, and three

"fingers breadth long, and a little hooked at the end. Its

head is large and flatted at the top, and its back, breaft,

belly, and tail white, but with a little blacknefs juft in the

middle of the back, and in the long feathers of the wings.

Its legs and feet are white, and its hinder toe very ihort.

Its mouth opens to a great width ; it feeds on filh, and is

common on fome of our coafts. Ray's Ornitholog. p. 261.

GULYAVAN, in natural hiftory, a name given by the peo- ple of the Philippine iilands, to a very beautiful bird, com- mon-in that part of the world ; it is of the fize of a turtle dove, and. is very beautifully variegated with black and gold coloured feathers. It feeds on fruits.

•GUM.- Apples, in Languedoc, and fome other parts of France. The juice of apples will fometimes exfudate thro* their rind, and congeal all about them in form of a clear white gum, hard like ice, by reafon of its being foon dried in the fun into a thin cake. The people call fuch an apple, pom?ne gelee, or a frozen apple. It is very common to fee apples covered in part with this gu?n in leveral fpecks ; but it is more rare to meet with them wholly fo. The gum is in- fipid to the tafte.

We have one plant cultivated In fome gardens, which yields in the heat of fummer fuch another white icy and taltelefs gutn. This is the common rhubarb, of the ftaiks of the leaves of which tarts are made. The ribs of the larger - leaves of this plant, in June and July, are covered with large tranfparcnt drops of this gum, and an ounce of it may be fometimes collected from a finglc plaut. Philof. Tranf. N' J. 224.

The common. plums and floes in our hedges alfo afford the fame clear and taltelefs white^aOT. It they are wounded on purpofe for it, they ufually throw more or lefs of it out at the wound ; but this is after fome time, and is not in fo large quantity as what they naturally throw out. The com- mon laurel alfo 'affords a little transparent white and taltelefs ~gum of no ill effect, though its leaves are poifonous. And it feems upon the whole, that this clear juice is not peculiar to apples or to two or three plants only ; but that a great number, even moff of them, do contain it, if we knew by what means to get it of them.

Gnu-Boils, a morbid affection of the gums, called by the writers of forgery parulides. Thefe are of different degrees, and ufually arife from pains in the teeth. They are to be t?eated by difcutients or other inflammatory tumors, but if thefe fail or the diforder is neglected, it ufually terminates in an abfeefs or fiftula. Sage, camomile and elder flowers, boiled in milk and water, make a good gargarifm to be held in the mouth, and the remaining herbs may be fowed up in a bag to be kept hot to the cheek. A half roafted fig is a very .good internal application, and when the foftnefs of the tumor ihews that the matter is fuppurated, it ought immediately to be opened by the lancet, to prevent the matters lodging there, and eroding the bone, and producing a fiftula or"ca- ries. After it is opened, the matter fhould be gently preffed out with the fingers, and the mouth frequently 3 warned with red wine mixed with a decoction of vulnerary herbs till it is well. When the ulcer has penetrated deep, it will be neceffa- ry to inject the fame liquors with a fyringe, and comprefs the part by a proper external bandage, to make the bottom part heal firft ; and when it is already become fiftulous, and has callous edges, it may then often be cured by injecting tinaure of myrrh, and elixir proprietatis, continuing this for jome time. If all thefe prove ineffeaual, the fiftula rnuit be laid open by incifion, and the caries removed by medicines, cauftics, or the adual cautery. If this pro- ceeds, as fometimes it does, from a carious tooth, this is firft ,

4 1

to be drawn before any thing elfe can be done ; and it is £ good rule in thefe cafes always to be rather too foon than too late in laying them open. Heijhr's Surg. p. 463. Sec alfo Schelhamqier de Epulide.

Gum Lace. See the article Lacca, Cycl. and Supplem.

GUMMA, a fort of venereal excrefcence on the periofteum of the bones.

GUMMI Olivai olive gum, in the materia medica of the ami- ents. We meet with this name given to a drug they fometimes ufed in coughs, and difeafes ot the lungs. Many have been, of opinion, that the antients exprefled no other than the common oil of olives by this name, and fome things which they have faid about it, feem to give countenance to this opinion, though a very ftrange name be warranted by it for a very common thing. But there are many paflages in other of the antient writers, which are wholly incompatible with this opinion, and {hew that fomething elfe, not oil, was meant by it. Avifenna defcribing the common ftorax tells us, that fome called the gummi oliva by its name. It could not be that any could call oil and ftorax by the fame name. There is no fort of refemblance or affinity between the two things ; but the Greek authors feem to fet us right in this matter: they all defcribe a fubftance under the name of SdK^va EXaias, the tears of the olive tree, which feems to have been a thing wholly different from oil, and rather a concreted gum thus called j as the galbanum, ammoniacum, and other gums in common ufe with us, are called the am- moniacum in tears, &c.

The Greek authors meant the fame fubftance by this name, that the Latins, or at leaft the generality of them did by gummi oliva ; and they exprefsly defcribe this as a gum, and diftinguifh it from the oil by faying, that it is not the exprefled juice of the fruit of the elaia, or olive, but the fpontaneous exfudation of the tree.

This gummi olea, or oliva, might very well be compared to the Jiorax jhgonius, or ftorax in tears, or drops ; and the in- accuracy of the early writers among the Arabians might authorize its being called by the fame name ; that it is not likely that any Ihould call a gum and an oil by the fame name.

GUN(CycL) — The advantage of large £««j,orcannon ? over thofe of a fmaller bore, is generally acknowledged. This advantage arifes from feveral circumftances, particularly in diftant can- nonading. The diftance to which larger bullets fly with the fame proportion of powder, exceeds the flight of the fmaller ones, almoft in proportion to their diameters ; fo that a thirty two pound ihot for inftance, being fomewhat more than fix inches in diameter, and a nine pound ihot but four inches, the thirty two pound fhot will fly near half as far again as that of nine pound, if both pieces are fo elevated as to range to the fartheft diftance poffible. The reafon of this is, the extreme great refiftance of the air, which is fuch, that the diftances to which bullets fly, is more regu- lated by this refiftance, than by the velocity they receive from the powder : and the larger bullets are lefs refilled in proportion to their weight, than the fmaller ; fo that their respective ranges are found to be nearly in the proportion of their diameters, as before mentioned a. [* Robins, propof. for increaf. the ftrength of the navy. p. 2, 3.] This advantage in the range of the heavier bullet, will not eaidy be counterbalanced by increafing the charge of powder allotted for the fmaller bullet. For though the fwiftnefs of this laft, at it's iflliing from the piece, may be thereby greatly increafed, yet the diftance to which the bul- let will fly is thereby but little influenced : as all this increafe of velocity is foon taken away by the refiftance of the air, which increafes much fafter b. This affertion might feem a paradox, but it is irrefragably eftablifhed by fome experi- ments maue by the French c. [ b Ibid. p. 4. ( Ibid. p. 4. not.]

Another and more important advantage of heavy bullets is, that with the fame velocity they break holes in all folid bo- dies, in a greater proportion than their weight. Thus a twenty four pound ihot will, with the fame velocity, break out a hole in any wall, rampart or folid beam, in which it lodges above eight times larger than will be made by a three pound fhot. For the great mot will penetrate to above twice the depth that the fmall one will, and lefs of the ca- vity it makes will be filled up again by the fp ring of the body pierced d. [ d Ibid. p. 6. J

Large cannon alfo by carrying the weight of their bullet, |a grape or lead ihot, may annoy the enemy more effectually than could be done by ten times the number of fmail pieces e. [ c Ibid. p. 7.]

The author here quoted, has propofed to change the fabric of all the pieces employed in the Britifh navy, from the twenty four pounders downwards ; fo that they may have the fame or lefs weight, but a larger bore. He thinks the thirty two pounders in prefent ufe, would be a proper mo- del for this purpofe. Thefe being of fifty two or fifty three hundred weight, have fomewhat lefs than an hundred and two thirds for each pound of bullet. And that this propor- tion would anfwer in fmaller pieces in point of ftrength, feems clear from thefe confederations. 1. That the ftrength of

iron