REF
ll E F
silk, cotton, &c. Reeling is performed in diliferent ways, and on.different engines.
RE-EN'i RY, in law, signifies the resuming or retaking thatpossession which any one had lately foregone ; as where a personmakes a lease of lands to another, the lessor thereby {puts the pos-session, and if the lessee covenants that upon non-payment of therent reserved, the lessor may lawfully re-enter, being’’as much asit was conditioned for the lessor to take the land again into hishands, and recover the possession again by his own act without theassistance of the law.
REERSOE, an island of Denmark, in the Great Belt , near thecoast of Zealand . Lon. 11. 19. E. Lut. 55. 33. N.
REES, a strong town of France , in the department of the Roer,and late duchy of Cleves, S miles E, of Cleves. Lon. (5. 4. E.Lat. 31. 50 N.
Rees ui, Ain, a town of Asiatic Turkey, in Diarbckir, 80 milesS. of Diarbeck.
REEVING, in the sea-language,, the putting a rope througha block : hence to pull a rope out of a block is called unreeving.
RE-EXCHANGE, in commerce, a second payment of theprice of exchange, or rather the price of a new exchange due upona bill of exchange that comes to be protested, and to be refundedthe bearer bv the drawer or indorser.
REFECTION, among ecclesiastics, is a spare meal or repast,just sufficing lor the support of life: hence the hull in convents,and other communities, where the monks, nuns, &c. take their re-fections or meals in common, is called the refectory.
REFERENCE, in writing, &c. a mark relative to anothersimilar one in the margin, or at the bottom of the page, wheresomething omitted in the text is added, and which is to be insertedeither in reading or copying.
REFINING, in general, is (he art of purifying a thing; in-cluding not only llie essaying or refilling of metals, but likewisethe depuration or clarification of liquors. See Clarification,Metallurgy , and Pharmacy.
REFLECTION, in philosophy, is the return or regressive mo-tion ot a moving body, occasioned by some obstacle which hin-dered it from ptirsu ng its former direction.
Reflection is also used, figuratively, for an operation of themind, whereby it turns its view backwaids as it were upon itself,and -makes itself and its own operations the object of its dis-quisition; and .by contemplating the manner, order, and laws,which it observes in perceiving ideas, comparing them together,reasoning, &c. it frames new ideas ot the icialious discoveredtherein. See Metaphysics.
Reflection, Circular Instrument of, an instrument formeasuring angles to a very great degree <ff accuracy. It was in-vented by the celebrated astronomer Mr. Tobias Meyer, of Got-tingen , principally with a view to do away the errors of the divi-sions ot the limb ; and has since been much improved by the che-valier de Borda, and M. L II. de Magellan. This instrumentis particularly applicable to the measuring of the distances of theheavenly bodies, and was used by the French in their part of theoperation for determining the difference of meridians of Paris andGreenwich. This instrument is well described by Mr. Mackay,in his Treatise on the Longitude, vol . i. p. 44,
Reflection of the Rays of Light, in catoptrics, is their re-turn, after approaching so near the surface of bodies as to be there-by repelled or driven backwards. For the causes of reflection,see Optics. For the application of the doctrine of reflection tomirrors, see Optics, Mirror, and Burning Glass. Sir IsaacNewton is of opinion, that light in its passage, from the luminousbody, is disposed to be alternately reflected by, and transmittedthrough, anv reflecting surface it may meet; and this dispositionbe calls tits of easy reflection, and easy transmission. Thus, if wetake the distances as the numbers 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,then at the distances 0, 2, 4, 6, 8, &c. the light will be trans-mitted ; and, at the distances 1, 3, 3, 7, 9, &o. it will be reflectedm coloured rings. To observe tiie order of the colours, he madevise o; two object-glasses, one a plano-convex, and the other a dou-ble-convex, of the same sphericity' on both sides, of fifty-one feetfocal distance ; and upon this he laid the plane side ot the other,;piessing them slowiy toge her to make the colours successivelyemerge in-uie middle of the circles, and then slowly lilted theUpper glass from the lower to make them successively vanish again
VOL. iv.— no. ,188.
C b, blue.
) r, white.
) d, yellow,(.e, red.
S q, green.
( r, red.
in the same place. Upon compression of the glasses, various co-lours would emerge and spread into concentric circles or rings ofdifferent breadths and tints encompassing the central spot. Theirform, when the glasses were most compressed, is delineated in.Elate CLVL fig. 4, where a is the central black spot, and the cir-cuits of colours from thence outwards as follows:
ff, violet. f/, purple.
| g, blue. | m, blue.
h, green. 34 n, green,
z, yellow. [ o, yellow,
p/t, red. [_/), red.
- ( s, greenish blue.
( t, red.
g j u, greenish blue. _ C y, greenish blue.
\ .r, pale red. \z, reddish white.
These rings were observed to be least when the eye was heldperpendicularly over the glasses in the axis of the rings: whereas,viewed obliquely, they became bigger, continually swelling as theeye was removed farther from the axis: and the coloured ringsmade in air, became much more distinct raid visible, when viewedin a dark room by the reflection of the coloured light of the prism.Tiie rings made by reflection of red light were manifestly biggerthan tiiose made by the bine and violet; and it was very pleasantto see them gradually swell and contract according as the colourof the light was changed. The motion was quickest in the red-,and slowest in the violet; and, by an estimation made of the dia-meters of the rings, the thicknesses of air in the places where therings are made by tiie limits of the seven colours, red, orange,yellow, green, blue, indigo, violet, successively in.order, were t»one another as the cube roots of the squares of the eight lengthsof a chord which sound the notes of an octave, that is, of the num-bers 1, $, •£> I- f> 4, t%> -£• These rings were not of various co-lours, as those made in die open air, but appeared all over of thatprismatic colour only with which it was illumined ; and by throw-ing the coloured light directly on the glasses, that which fell onthe dark spaces between the rings was transmitted through thaglasses without any variation of tiie colour. This appeared byplacing a white paper behind, on which the rings were painted ofthe same colour as those by reflected light, and of the bigness of '■their immediate spaces. Hence the origin of these rings is mani-fest; namely, that the air between the glasses, according to its va-rious thickness, is di-posed in some places to reflect, in others totransmit, the light of any one colour; and in the same place toreflect that of one colour, where it transmits that of another; inthe manner as you see represented fig. 3, where AB, CD, are theglasses, as before; and a, c, c, g, i, i, n, p, the parts of the beamtransmitted; and b, d,f, h, k, m, o, the parts of the beam reflected, making the coloured rings.
REFLEX, in painting, means those places in a picture whichare supposed to be illuminated by light reflected from some othebody in the same piece. Sec Painting.
REFLEX1TY, a word used by Mr. Brougham, to denote aproperty of light, which causes the different rays to be acted on by.bodies, and to begin to be refracted, reflected, inflected, and de-flected, at different distances. 'Phis property follows the samelaw, that the other optical properties of light follow ; the fed ravhaving most reflexity, and the violet least.
REFLUX , has the same meaning as the ebbing of the sea, andis opposed to flood, flux, or the flowing of the sea. See 'I ides.
REFORM, a change from worse to better, a re-establishmentor revival of former neglected discipline, or a correction of abusestherein.
REFORMATION, in general,, is an act of reforming or cor-recting an error or abuse in religion, discipline, ot the like , but isparticularly used for that great alteration in the corrupted system,of Christianity, or the separation of the Protestants bom the churchof Rome . T his reformation was first set on foot by Luther in1517. See Luther.
REFRACTION , in optics, the -change of direction whichhappens to the rays of light when they enter obliquely into a dif-ferent medium: "thus let an empty • vessel, as BCDE, (PlateCLV1. lig.G,) have a small object pcaced at its bottom at A ; andlet it be so situated as that the sight of the object may be inter-cepted by the side of the vessel, trom an eye placed at Q ; thenlet the vessel be filled with water, and the ray AB, which beforeCD • • live