CALORIC CALPRENEDE. 



819 



in contact with a body in which it is accumulated. 

 Common air and gases abstract it but tardily, while 

 wood, stones, and metals, acquire it more rapidly. 

 According to their power of conducting it off under 

 these circumstances, bodies are divided into conduc- 

 tors and non-conductors of caloric ; and, in general, 

 the power of conduction varies with the densities of 

 bodies. But this tendency of caloric to an equilibrium 

 is not established solely by the agency of intermediate 

 bodies or communication. A part of it moves through 

 the atmosphere, like light, in right lines, and with 

 immeasurable velocity, and has, therefore, been called 

 radiant caloric. The comparative quantities lost by 

 radiation and by conduction may be approximated by 

 observing what time it takes to cool any body through 

 the same number of degrees in air and in vacua. 

 Thus doctor Franklin imagined he had ascertained 

 that a body, which requires five minutes to cool in 

 vacua, will cool in air, through the same number of 

 degrees, in two minutes. Count Rumibrd's experi- 

 ments, with a Torricellian vacuum, give the propor- 

 tions of five to three. 



Radiant caloric passes only through transparent 

 mediums, or free space. When, in its passage, its rays 

 impinge upon the surface of a solid or a liquid sub- 

 stance, they are either reflected from it, and thus 

 receive a new direction, or they lose their radiant 

 form altogether, and are absorbed. In the latter 

 case, the temperature of the receiving substance is 

 increased ; in the former, it is unchanged. 



The nature of the surface of a body has been found 

 to influence powerfully both the radiation and absorp 

 tiori of caloric. The energy of calorific emanation 

 from a cubical tin vessel, coated with different sub- 

 stances, and containing warm water (as determined 

 by the differential thermometer of Leslie), gave, with 

 a covering of 



Lampblack . .100 



Isinglass . . 75 



Tarnished lead . . 45 

 Polished iron ... 15 



Tin-plate, gold, silver, or copper . 12 



Similar results were obtained simply by noting the 

 rates of cooling in vessels of similar shapes and capa- 

 cities with various surfaces. Useful lessons have been 

 derived from these discoveries. Tea and coffee-pots, 

 which are intended to retain their heat, are made of 

 bright and polished metals ; and steam pipes, intended 

 to convey heat to distant apartments, are kept bright 

 in their course, but darkened where they reach their 

 destination. The power of different surfaces to absorb 

 caloric was found, by coating one of the bulbs of the 

 differential thermometer successively with different 

 substances, and presenting it to an uniformly heated 

 substance, to follow the same order as the radiating 

 or projecting quality. 



With regard to combined caloric, it has been shown 

 that solids, during liquefaction, imbibe a quantity of 

 caloric, which ceases to be. obvious, both to our senses 

 and to the thermometer. The same is also true of 

 solids and liquids in their conversion into vapours or 

 gases ; a portion of caloric, which is essential to the 

 elasticity of the new product, ceases to become appar- 

 ent. Whenever this effect takes place, cold is said to 

 be produced ; by which we are only to understand the 

 passage of caloric from a free to a latent form. The 

 reverse of these phenomena has also been satisfcic 

 torily established ; viz. when the density of bodies is 

 increased, either by chemical or mechanical means, 

 caloric is evolved. For example, a high temperature 

 is produced by mingling cold sulphuric acid and 

 water ; metals become intensely heated by the aug- 

 mentation of their density through hammering ; li- 

 quids, by becoming solids, or gases by conversion into 

 liquids, also evolve caloric. A pound of water con- 



densed from steam, will render 100 pounds of water 

 at 50 warmer by 11 ; whereas, a pound of boiling 

 water will produce the same rise of temperature in no 

 more than about 13*12 pounds ; and, since steam and 

 boiling water affect the thermometer in the same man- 

 ner, this effect can be produced only from the exis- 

 tence of a much greater quantity of caloric in the for- 

 mer than in the latter. 



The sources of caloric are six ; viz. the sun's rays, 

 combustion, percussion, friction, the mixture of dif- 

 ferent substances, and electricity. 



CALORIMETER ; an instrument to measure the capa- 

 city of a body for caloric, or its specific caloric. The 

 thermometer (q. v.) measures merely the variations of 

 temperature, or sensible heat. The body in the calo- 

 rimeter is placed in the innermost of three concentric 

 vessels, the two outer ones containing ice ; the 

 quantity of water produced by the cooling of the 

 body a given number of degrees, determines its spe- 

 cific caloric. This instrument was invented by La- 

 voisier and Laplace. In the C. invented by Rumford, 

 water is used the capacity of the body is determined 

 by the number of degrees which the temperature of 

 the water is raised, in cooling the body a given num- 

 ber of degrees. 



CALORI MOTOR. See Galvanic Battery. 



CALOTTISTS, or the REGIMENT DE LA CALOTTE; a so- 

 ciety which sprang up at Paris, in the last years of 

 the reign of Louis XIV., and formed a regiment un- 

 der the name La Calotte, signifying a flat cap of a pe- 

 culiar shape, which was the symbol of the society. 

 All were admitted whose ridiculous behaviour, odd 

 character, foolish opinions, &c., had exposed them to 

 public criticism. They had a singular coat of arms, 

 on which was the sceptre of Momus, with bells, apes, 

 rattles, &c. : on their principal standard were the 

 words " Pavet Momus, luna influit." Every one who 

 made himself particularly ridiculous received letters- 

 patent, and those who were most angry were most 

 laughed at. On the death of Torsac, the colonel of 

 the Calottists, the eloge (a spirited satire on the aca- 

 demical style,) which the Calottists pronounced on 

 this occasion, was suppressed. Aimon, colonel of 

 the guards, hastened to marshal Villars with their 

 complaints, and concluded with the words, " My lord, 

 since the death of Alexander and Caesar, the Calot- 

 tists have not had any protector besides you," and the 

 order was retracted. They became, however, too 

 bold, attacked the ministers, and even foreign kings ; 

 and the regiment was, in consequence, dissolved. Of 

 a similar character is the Academy of Fools, which, for 

 many years, has existed in Duisburg. Some act of 

 folly is necessary to procure a man admission as a 

 member. 



CALOYERS ; Greek monks, who chiefly reside on 

 mount Athos, and lead a very solitary and austere 

 life, eating no meat, and observing the fasts of the 

 Greek church very rigidly. They" do not even eat 

 bread, unless they have earned it. During their 

 seven weeks of Lent, they pass the greatest part of 

 the night in weeping and lamentations for their own 

 sins and for those of others. The Turks sometimes 

 call their dervishes by this name. 



CALPK. See Abyla and Gibraltar. 



CALPRENEDE, Gauthier de Costes de la, a French 

 romance writer, was born in Tolgou, in Gascony, and 

 died at Paris in 1663, in the office of royal chamber- 

 lain. He was one of the authors who, in the 17th 

 century, brought into fashion a new kind of volumin- 

 ous and long-spun romances of chivalry. Events 

 from tlie Greek and Roman history were treated in 

 the spirit and manner of the old romances of chivalry. 

 C. wrote Cassandra, in ten vols., Cleopatra, in twelve 

 vols , Pharamond, in seven, besides some tragedies. 

 His tragedies obtained little reputation by the side 



