R E F 



RET 



the ordiiiaLcs H, I, N, O, P, witli fufficicnt accuracy for 

 the purpofc here intended. All thefe being applied to the 

 middle of the fpaces whicli belong to their rei'pedlive co- 

 lours, we have the figure G R Q G, reprefcnting what may 

 be called the fpeftrum of illumination. 



We are now, in the fame manner, to find a figure to ex- 

 prcfs the heating power of the refrafted prifmatic rays, or 

 what may be called the fpeftrum of heat. In order to de- 

 termine the length of the bafe, Dr. Herfchel examined the ex- 

 tent of the invifible rays, and found, that at a diftancc of two 

 inches beyond vifiblc red, his thermometer, in a few minutes, 

 acquired I^ degree of heat. The extent of the coloured 

 fpettrum at that time, or the line which anfwered to G Q in 

 his figure, meafured 2.997 inches. If two inches had been 

 the whole of the extent of the invifible part, it might be 

 itated to be in proportion to the viiible one as 2 to 3 ; but 

 ■we are to make fome allowance for a fmall fpace required 

 beyond the laft ordinate, that the curve of the heating power 

 drawn through it may reach the bafe ; and indeed, at 25inchcs 

 beyond vifible red. Dr. Herfchel could Itill find i degree 

 of heat. It appears therefore fufficiently fafe, to admit 

 the bafe of the fpcftrum of heat A Q, to be to that of the 

 fpeftrum of light G Q, as 5^ to 3 ; or, conforming to the 

 Newtonian figure before mentioned, the bafe of which is 

 3.3 inches, as jyf to 33. Now, if we aflame for the 

 maximum of heat, an ordinate of an equal length with that 

 which was fixed upon for the maximum of light, it will give 

 us a method of comparing the two fpeclra together. Accord- 

 ingly, Dr. Herfchel has drawn the feveral ordinates B, C, D, 

 E, F, G, H, 1, K, L, M, N, O, P, of fuch lengths as, 

 from experiments made on purpofe, it appeared they fhould 

 be, in order to exprefs the heat indicated by the thermo- 

 meter, when placed on the bafe, at the feveral ftations 

 pointed out by the letters. 



A mere iufpeftion of the two figures, which have been 

 drawn as lying upon one another, will enable us now to fee 

 how very differently the prilm difperfes the heat-making 

 rays, and thofe which occafion illumination, over the areas 

 A S Q A, and G R Q G, of our two fpeClra ! Thefe 

 rays neither agree in their mean refrangibility, nor in tlie 

 fituation pf their maxima. At R, where we have moll 

 light, there is but little heat ; and at S, where we have 

 moft. heat, we find no fight at all ! 



REFRESHMENT, Quarters of. See Quarters. 

 REFRET, Fr. the burden of a fong. This word is 

 only to be found in the fecond folio edition of Bailey's 

 DiAionary, 1736. In no French diftionary is there au- 

 thority for it. Cotgrave, Dift. du Vieux Langage ; Tre- 

 voux, Ditt. de 1' Academic ; and Gloflaries, have been con- 

 fulted in vain. 



REFRIGERANT, Refrigerative, in Medicine, or 

 cooling! irom frigus, cold, an appellation given to fuch re- 

 medies as were iuppofed to poifefs a power of cooling the 

 internal parts. Hence all diluents, fuch as ptifan, gruel, 

 and other thin drinks, vegetable and mineral acids, neutral 

 falts, and other fubltances, which are deftitute of ftimu- 

 lating qualities, and communicate a lenfation of coolnefs to 

 the tongue and throat, have been confidered as refrigei"ant. 

 As they have no aftual power of generating cold in the 

 animal body, the term is fomewhat incorrecfl ; but as it ex- 

 preffes the oppofite quality to that of ftimulating, which is 

 ufed alfo as fynonimous with heating, it is liill retained, and 

 applied to diet, drink, and medicine of a non-ftimulant qua- 

 lity. In this fenfe, the term is nearly fynonimous withy?- 

 dative. 



Whatever, in faft, increafes the circulation, increafes the 

 heat of the body, and -vice iierfd; potentially, therefore, 



all fed.itive medicines may be faid to be refrigerant. The 

 ufe of refrigerants will thence be inferred to be proper 111 

 all thofe cafer, in which there i£ an ovcr-excitemcnl of tli'- 

 circulation, cither locally or generally ; fuch as local inflam- 

 mations, febrile difeafes, hemorrhages, and the like. In 

 the cafe of external inflammations, indeed, aftual refrige- 

 ration may be produced, by the application of cold fub- 

 ftances, water or ice, or by the abftraclion of heat by 

 means of evaporation ; both of which afford the means tf 

 direftly diminifhing the aftivity of the veffc-ls of the parf. 

 Thus, in burns and fcalds, the pain is inftantly relieved, 

 and the inflammation effectually reduced, by the iinmerfion 

 of the part in cold water, if fufficiently perfevered in. But 

 in refpeft to internal refrigerants, their operation is ot a 

 negative kind, and confills rather in the removal of uneafy 

 fenfations, and in the exclufion of llimulant fubftances, than 

 in the ac\ual iuppreffion of increafed aftion. See Se- 

 dative. 



REFRIGERATION, denotes the aft of cooling, or 

 the abftraftion of heat from various fubltances. This is 

 effefted in a variety of ways, and for various purpofes of 

 domeiUc ufe and of ai"t ; and the dcg. ie of cold that is 

 produced is eftimated by an inftrument called the thermo- 

 meter, which fee. Under this head it is needlefs to repeat 

 the principles of refrigeration, and the different proceffes 

 that are ufed for this purpofe, which are amply ftated and 

 defcribed under the articles Cold, Congelation, Cooling, 

 Freezis(;, Heat, Ice, IcK-houfes, &c. 



REFRIGERATORY, Refrigeratorilm, in Che- 

 m'lflry, a copper veffel filled with cold water, foldered round 

 the capital of an alembic, to cool and condenfe the vapours 

 raifed thither by^ the fire, and to convert them into a liquor, 

 to be difcharged thence through the beak. See Alembic. 

 The water in the refrigeratory is to be changed from time 

 to time, as it begins to grow warm. 



Sometimes they content themfelves with wrapping.a wet 

 cloth about the head of the alembic, iiiftead of a refrige- 

 ratory ; but the more ufual method now is, to fupply the 

 place of the refrigeratory by a worm, or fpiral pipe, run- 

 ning through a tub of cold water. 



Diftillation chiefly confills in evaporation and refrige- 

 ration. See Distillation. 



REFUGE, Refugium, in our Old Cujioms, a fanc- 

 tuary, or ajylum ; which fee refpeftively. 



At Paris there is an hofpital called the Refuge, in whicli 

 diffolute women are fhut up. 



Refuge, Cities of, in Scripture Hi/lory, fix cities felefted 

 from the 48 appropriated to the relidcnce of the Levites, 

 which were appointed for the protection of perfons from the 

 rigour of the law, who were chargeable wth involuntary 

 homicide. Some have fuppofed that all the cities of the 

 Levites were afyla ; but it appears from Numb. xxxv. 6. 

 that only fix of them were appointed to this ufe. Thefe 

 afyla were intended not only for .lews, but for Gentiles, or 

 for itrangers who dwelt among them. (Numb. xxxv. 15.) 

 They were not defigned as fandtuaries for wilful murderers 

 and all forts of atrocious villains among the Jews, as they 

 were among the Greeks and Romans, and as fuch places 

 have fiiyre been in Roman Cathohc countries, but merely 

 for fecuring thofe who had been guilty of involuntary homi- 

 cide (Deut. xix. 4 — ic.) from the effeds of private re- 

 venge, until they were cleared by a legal procefs. It is ob- 

 fervable, that the Ifraelites are commanded to " prepare the 

 way," that is, to make the road good, " that every flayer 

 may flee thither," without impediment, and with all expe- 

 dition. (Deut. xix. 3.) By having good roads to them, 

 at leall 32 cubits, or about 48 feet in breadth, and bridges 



wherever 



