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THE STANDARD DICTIONARY OF FACTS 



oxygen of the air being the universal method of 

 getting heat and light, and as when the action 

 takes place the fuel is said to burn or undergo 

 combustion, the latter term has been extended 

 to those cases in which other bodies than carbon 

 for example, phosphorus, sulphur, metals, 

 etc. burn in the air or in other substances than 

 air for example, chlorine. Though the action 

 between the uas and the more solid material, 

 1. WOOO, charcoal, of whose combination 

 combustion is the result, is mutual, the one 

 having as much to do with the process as the 

 other, yet the former, as oxygon, chlorine, iodine, 

 and the compounds which they form with each 

 other and with nitrogen, have received the name 

 of supporters of combustion, while to the latter 

 the term combustibles has been assigned. 



Spontaneous Combustion is the ignition of a 

 body by the internal development of heat with- 

 out the application of fire. It not unfrequently 

 takes place among heaps of rags, wool, and cotton 

 when lubricated with oil; hay and straw when 

 damp or moistened with water; and coal in the 

 bunkers of vessels. In the first case the oil 

 rapidly combines with the oxygen of the air, 

 this being accompanied with great heat; in the 

 second case the heat is produced by a kind of 

 fermentation; in the third by the pyrites of the 

 coal rapidly absorbing and combining with the 

 oxygen of the air. The term is also applied to 

 the extraordinary alleged phenomenon of the 

 human body being reduced to ashes without the 

 direct application of fire. It is said to have 

 occurred in the aged and persons that were fat 

 and hard drinkers ; but most chemists reject the 

 theory and altogether discredit it. 



Comet. A celestial body presenting a 

 nebulous aspect, and traveling under the sun's 

 attraction. Many of these bodies are distin- 

 guished by a remarkable tail-like appendage. 

 The greater number of those hitherto known have 

 revolved round the sun on a path whose observed 

 portion belonged to an exceedingly elongated 

 ellipse, or was even parabolic or hyperbolic. A 

 few, however, travel in closed orbits around the 

 sun in known periods. Among the most remark- 

 able comets in recent times were those of 1780, 

 1807, 1811, 1815, 1819, 1825, 1843, 1847, 1858, 

 1861, and 1874. We know so little respecting 

 the physical conditions of comets that it would 

 be hazardous to speculate at present concerning 

 their real nature. A theory of great ingenuity, 

 and (what is novel in this branch of speculation) 

 founded on physical experiments which really 

 seem to have some bearing on the subject, were 

 put forward by Professor Tyndall, who is dis- 

 posed to regard the tails of comets as resulting 

 from the formation of a species of actinic cloud 

 by the action of the solar rays, after their charac- 

 ter has been altered during their passage through 

 the comet's head. At present, however, it is 

 difficult to say whether such a theory is well or 

 ill founded. 



Conchology. The science of shells, that 

 department of zoology which treats of the nature, 

 formation, and classification of the shells with 

 which the bodies of many mollusca are pro- 

 tected ; or the word may be used also to include 

 a knowledge of the animals themselves, in which 

 case it is equivalent to malacology. In systems 



of conchology shells are usually divided into 

 three orders: Univalves, Bivalves, and Multi- 

 valves, according to the number of pir. 

 which they are composed. 



Conductor. A body capable of transmit- 

 ting the electric fluid. It is called also a non- 

 electric; for, unless insulated, it will not exhibit 

 electrical excitement, the electricity beiiii; car- 

 ried off along it as fast as it is communicated to 

 or excited upon it. The metals are the best 

 conductors; resinous substances are very bad 

 ones. Bodies incapable of transmitting elec- 

 tricity are called non-conductors; and, because 

 electricity may be communicated to or excited 

 upon them, without artificial insulation, they are 

 termed electrics. There is no body a perfect 

 conductor, or a perfect non-conductor. The 

 non-conducting power depends very much on 

 the extent of non-conducting surface. In fric- 

 tional electricity, the best conductors are the 

 metals, as before stated; after which come 

 graphite, sea-, spring-, and rain-water. Ice is 

 a worse conductor than fluid or water. Alcohol, 

 ether, paper, dry wood, and straw, are also weak 

 conductors. Shellac, wax, amber, and sulphur 

 become conductors when fused; and glass at a 

 red heat conducts readily. A conductor is said 

 to be insulated when it rests upon non-conduct- 

 ing supports. A lightning-conductor is a pointed 

 metallic rod fixed to the upper parts of build- 

 ings to secure them from the effects of lightning. 

 It is connected with the earth, or, what is better, 

 the nearest water, by a good conductor, which 

 is sufficiently thick not to be melted in trans- 

 mitting the electricity; and which, where at- 

 tached to the wall, is insulated by non-conduct- 

 ors, so that the electricity may not be diverted 

 to the building, instead of passing harmlessly 

 away. This useful instrument was invented by 

 Franklin in 1755. 



Congregationalists. A large and in- 

 fluential Christian sect, called also Independents 

 in England, because they hold that every single 

 congregation of Christians, when properly con- 

 stituted with deacons and a pastor, forms an 

 independent body, competent to its own direc- 

 tion and government, without interference from 

 any other church, or any presbyteries, bishops, 

 etc. They therefore hold that each congrega- 

 tion has inherent in itself power to fix its own 

 tenets and form of religious worship, and to ex- 

 ercise ecclesiastical government. They hold a 

 Christian Church to be a congregation of true 

 believers; i. e., persons who both openly pro- 

 fess their faith in the essential doctrines of the 

 Gospel, and evince the earnestness of their be- 

 lief by a corresponding change of disposition 

 and demeanor. The doctrines of the Congrega- 

 tional Churches are almost identical with those 

 embodied in the Articles of the Presbyterian 

 Church, interpreted according to their Calvin- 

 istic meaning. They disavow all subscription 

 to creeds, confessions, or articles of faith; never- 

 theless, they are distinguished by a singular 

 degree of uniformity in faith and practice. As 

 to the origin of Independency, it is probable, 

 that some conventicles were secretly established 

 in England soon after the accession, of Elizabeth ; 

 but the first prominent advocate of Congrega 

 tional principles appeared in 1580, in the person 



