Page:Cyclopaedia, Chambers - Volume 1.djvu/297

 CAM

.Mi )

If A about a Woman with Child, made hef Delivery fafe. That its tight Jaw remov'd all Fear ; that its Tail ftopp'd the Courfe of Rivers : Phny allures us, Democritus had compos'd a whole Book of fuch follies.

Cimeleos, in Aftronomy, is one of the Conftellations of the Southern Hemilphere, added by the Moderns. See Constellation.

CAMELOT, or CAMLET, a Stuff, fometimes of Wool, fometimes Silk, and fometimes Hair, efpecially that of Goats, with Wool or Silk ; in fome, the Warp is Silk and Wool twitted together, and the Woof Hair. England, France, Holland, and Flanders, are the chief Places of this Manufafture ; Sruxels exceeds 'em all in the Beauty and Quality of its Camelots : Thole of England are reputed the fecond.

Figured Camelots, ate thofe of one Colour, whereon are ftamp'd various Figures, Flowers, Foliages, ii?c. by means of hot Irons, which arc a kind of Moulds, pafs'd, together with the Stuff, under a Prefs. Thefe are chiefly brought from Amiens and Flanders : the Commerce of thefe, was antiently much more confidetable than at prcfent. Water Camelots, thofe which, after weaving, receive a certain Preparation with Water; and areaftcrwards pafs'd under a hot Ptefs, which gives 'em a Smoothnefs and Luflre. Waved Camelots, are thofe wheteon Waves are im- prcts'd, as on Tabbies, by means of a Callendar, under which they are pafs'd and repafs'd feveral times. See Cal- lendar.

The Manufacturers, K?c. of Camelots, are to take cate they don't acquire any falfe or ncedlefs Plaits ; it being al- moft impoftible to get 'em out again : This is notorious, even to a Proverb ; thus we lay, a Perfon is like Camlet, he has taken his 'Plait.

Menage derives the Word from tamhdot, a Levantine Term for Stuffs, made with a fine Hair of a iurkijll Goat : Whence the Word Turkijb Camelot. Others call it Capel- lote, from Cafelle, She-Goat. Sochart makes Zambclot, a Corruption of the Arabic Giamcl, or Camel. Othets fetch Camelot from the bare Latin Camelus : So that Camelot fhould properly fignify, a Stuff made of Camels Hair.

CAMERA OBSCURA, 'Dark Chamber, in Opticks, a Machine or Apparatus, reprefenting an Artificial Eye ; whereon the Images of External Objects are exhibited dif- tinctiy, and in their native Colours; either invertedly or ii erecl. See Artificial Eye.

The firft Invention of the Camera Obfcura, is afcrib'd to Sap. 'Porta.

The Ufe of the Camera Obscura is manifold : It ferves to very good Purpofes in explaining the Nature of Vifion ; and hence it is that fome call it the Artificial Eye. It affords very diverting Specfaclcs ; both by exhibiting Images per- fectly like their Objects, and each cloth 'd with their na

CAM

will be delineated fayettedly. * 1 If -1 ^S£i °$£%

to have 'em appear ereft, 'tis done either bf mea fof

f S is? p n ac K ed between i ,? e Centre «* ^ Fo- ot the firit Lens - or by receiving the Image on a Plane Sie- culum, inclm d to the Horizon, under an Ingle of 45' ? » « by means of two Lens's included in a Draw Tube* in lieu JW?d. ft&S fthe, Aperture don't exceed the Bignefs of a Ss at^usU "f W P* fe »^. even tho thtre be no

the Obje£ts be illumiu'd by the Sun's Light They will be fl.ll brighter ,f the Speilatot firft ftay^a quarter* of an Hour in the Dark. Care muft be likewife taken, that no Light efcapo thro any Chinks j and that the Wall ben't too much .Uumin d. Farther, the greater Diftance there is between the Aperture and the WaB; the larger and more diflinft will the Images be, but, heRays becoming, thus,

till at length it becomes invifible

ConftruElton of a portable Camera Obscure t Pro-

Fi ,*, " f e ,b p ' M B r° X ,° f dl >' Wo ° d . (Tab. Opticks, Fig. 17.) of the Figure of a Parallelolipiped 5 its Breadth about 10 Inches and its length two or more Feet ; accor- ding to the different Magnitude of the Diameter of the Lenss. 1. In the Plane BD fit a Aiding Tube EF with two Lens s ; or, tofet the Image at a lefs Diftance from the lube, with three Lens's convex on both Sides: The Diameter of the two outer, or forwarder, to be . 6 °_ of a Foot ; that of the Inner lefs, v.g. »_.. 5. W Sdn the Cheffi, at a proper diftance from the Tube, let up an oil'd Paper perpendicularly, G H, fo as Images thrown upon fo may be feen thro. 4. Laflly, in I make a round Hole, it as a rerlon may look conveniently thro it with both Eyes.

It then the Tube be tutn'd towards the Obiefts (the Lens » being at their proper Diftance, to be determined by Experiment; the Objeas will be delineated on the Paper G H, erect, as before. '

Another Portable Camera Obscura

1. In the middle of zCiflula, or Cheft, (fab. Opticks, Fig. t8.) raife a little Turret, either round or fcuare HI, open towards the Objeft A B. i. Behind the Aperture incline a little plain Mirror a b, to an Angle of 4, < which may reflca the Rays, A« and Bb, upon a Lens convex on both Sides G, included in a Tube G L. 5 At the Dif- tance of the Focus thereof, place a Table cover'd with - er E F, to receive the Image

whiti

d by expreffing, at the fame time all, their its rife from

— - an Attack of this Kind ; wherein latter, no other Art can imitate. By or Signal to know one another by', They Sre a ins of this Inftrument, efpecially the third Contrivance Cbemifc, or Camife, over their Arms 1 ~ Perfon unacquainted with Defignini

tive Colours

Motions : whicn

me

under mention'd, a Perlon unacquainted with Defigning, will

be able to delineate Objeas to the laft accuracy and juft-

nefs ; and another well vers'd in Painting, will find many

Things herein to perfea his Art.

T'be 'theory of the Camera Obscura, is contain'd in the following Propofition.

If an Objea A B, (Tab. Opticks, Fig. 16.) radiate thro a fmall Aperture C, upon a white Wall oppofite thereto ; and the Place of Radiation behind the Apetture bCa be dark : the Image of the Objeft will be painted on the Wall, in an inverted Situation.

tDemonft. For the Aperture C being very fmall, the Rays ifl'uing from the Point B, will fall on b ; thofe from the Points A and D, will fall on a and d : wherefore, fince the Rays iffuing ftom the feveral Points are not confound- ed ; when rcfleacd from the Wall, they will carry with 'em a certain Species of the Objea, and exhibit its Appear- ance on the Wall. But fince the Rays A C and B C intcr- fea each other in the Apcrtute, and the Rays from the loweft Points fall on the higheft 5 the Situation of the Objea will of neccflity be inverted.

Corollary. Since the Angles at D and d are Right, and the Vertical ones at C are Equal ; B and b, and A and a, will be alfo Equal ; confequcntly, if the Wall, whereon the Objea is delineated, be parallel to it, a b : AB : : dC : DC. That is, the Height of the Image will be to the Height of fhe Objea ; as the Diftance of the Objefl from the Aper- ture, is to the Diftance of the Image from the fame.

CovfiruSion of a Camera Obscura, wherein the Ima- ges of External Objeas fhall be reprefentcd diftinctly, and in their genuine Colours, cither in an inverted, or an eteft Situation. 1. Darken a Chamber, one of whole Windows looks into a Place fet with various Objefls ; leaving only one little Aperture open in the Window. 2. In this Aper- rure fit a Lens, cither Plano-convex, or Convex On both Sides ; to be a Portion of a large Sphere. 3. At a due Diftance, to be detctmin'd by Experience, fpread a Paper,

NM make an oblong Apcrtute to lookthroueh ' * V ' "*

CAMISADE, in the Art of War, an Attack, by fur-

pme, in the Night, or at the Point of Day ; when the

Enemy are fuppos d a-bed. The Word is faid to have took

Shift,

CAMISARD, alerm whereby the French diftinguiflt the Calvmifis of the Ccvemics ; from a League or Faction tormd by em againft the French, in 1S88, and the fol- lowing Years; wherein either their Attacks were lb hidden, and had lo much of the Camifade in 'em; or they plunder'd Linen tor Shifts, or w.re Clothes that refembled Shifts, lo as to occafion the Name ; for Authors give all thefe De- rivations : to which may be added another more probable than any, viz. from Camis, a high, or beaten Road ; the Roads being infefted by the Camifards.

CAMP, a Spot of Ground, where an Army refts, intren- ches it felf, or plants a Piquet- Watch, to lodge fecure in Tents or Barracks. The Camp is fometimes cover'd by an Intrenchment ; fometimes only by the advantage of its Poft : Sometimes 'tis inclos'd with Chevaux de Frife, laid acrofs each other ; the ordinary Praaice of the old Prince of Orange. The chief Skill of a General lies in the Art of IncampmgweM : This the Romans were unacquainted with, till the War with Pyrrhus ; from whofe Camp they learn'd to model their own. Till then, they knew not how to poft themfelves to advantage, nor with any Order in their Camp. An Incampment, or fianding Camp, is always to have the Advantage of Water and Forrage, and the means of covering and retrenching it felf. Rhoe, defcribing the great Mogul's Camp, fays, 'tis 20 Englrjb Miles round, and con- - tains more Space than the largeft City in Europe. that 'tis compos'd of 800000 Men, and 40000 Elephants.

Flying.Ci.Mf, is a ftrong Body of Horle or Dragoons, to which are fometimes added Foot ; commanded uiually by a Licutcnant-General. This is always in Motion; both to cover the Garifons in Poffeffion, and to keep the Adver- fary in continual Alarm.

CAMPAIGN, a Military Term, fignifying the Space of Time duting which Armies are maintain'd every Year in the Field. The Germans begin their Campaign very lare j ufually waiting for Harvefl: : The French are always early, and begin fometimes in Winter,

CAM