C AL 



C AL 



of carbonate of lime, probably deposited 

 from calcareous springs. 



CA'LCULUS. The Latin term for a 

 pebble, used in former times for the pur- 

 pose of calculation. Hence it is applied 

 to any branch of mathematics which in- 

 volves calculation ; any, in fact, except 

 pure geometry. The several branches 

 are noticed under their specific names. 



CA'LENDAR (KaXew, to call). Ka- 

 lendar. A table of the days of the year, 

 arranged to assist the distribution of 

 time, and to indicate remarkable days 

 connected with devotion or business. 

 The term is derived from the Roman 

 Calends, or the first day of the month, 

 when the pontiffs called the people to- 

 gether, to apprise them of the days of 

 festival in that month. 



1. Roman Calendar. In the Roman 

 Calendar, as said to have been introduced 

 by Romulus, the year was divided into 

 10 months only, comprising altogether 

 304 days. The year of Romulus was, 

 therefore, of 50 days' less duration than 

 the lunar year, and of 61 days' less than 

 the solar year; and its commencement 

 of course did not correspond with any 

 fixed season. Numa Pompilius corrected 

 this calendar, by adding two months, 

 Januarius and Februarius, which he 

 placed before Mars. 



2. Julian Calendar. In order to render 

 the calendar still more correct, Julius 

 Caesar fixed the solar year at 365 days, 

 6 hours, comprising, as was supposed, 

 the period from one vernal equinox to 

 another. The six hours were set aside, 

 and, at the end of four years, forming a 

 day, the fourth year was made to consist 

 of 366 days. The day thus added was 

 called intercalary. See Bissextile. 



3. Gregorian Calendar. The Julian 

 Calendar was defective in this particular 

 — that the solar year, consisting of 365 

 days, 5 hours, and 49 minutes, and not 

 of 365 days, 6 hours, there was a dif- 

 ference, between the apparent year and 

 the real year, of eleven minutes. This 

 difference having amounted, in the year 

 1582, to ten entire days, Gregory XIII. 

 ordained that the 5th of October in that 

 year should be counted as (he 15th, thus 

 cutting off ten days from that year ; and 

 to prevent the recurrence of this error, it 

 was further determined that the year 

 beginning a century should not be bis- 

 sextile, with the exception of that begin- 

 ning each fourth century. This is the 

 Gregorian or New Style, as distinguished 

 from the Julian or Old Sttjle. 



65 



CALI'BRE. A French term, signifying 

 the bore of a cannon, and generally ex- 

 pressive of the diameter of any round 

 substance, and, figuratively, of the mental 

 capacities. The calibre of round bodies 

 is measured by what are called Callipers, 

 or calliper compasses, which are formed 

 with curved legs, furnished with knobs 

 instead of points. 



CA'LICO-PRINTING. The art of 

 dyeing cotton cloth, called calico from 

 Calicut in India, with one or more colours, 

 in certain parts, leaving the rest of the 

 material in its original state. 



CALITPIC PERIOD. In ancient 

 chronology, a correction of the Metonic 

 cycle of nineteen solar years, proposed 

 by Calippus. At the end of four of these 

 cycles, there is an excess of one day and 

 six hours over the number of lunations. 

 Calippus, therefore, proposed to quadruple 

 the Metonic period, and deduct a day 

 from the end of it by reducing the days 

 of one of the months from 30 to 29. 



CALLUS, or CALLOSITY. A term 

 applied to the thickening of enamel upon 

 a shell, resembling a tumour, as in the 

 inner lip of the olives, and near the 

 hinge of some bivalves. 



CALO'RIC (calor, heat). An ima- 

 ginary fluid, or condition diffused through 

 all bodies. In chemical language, caloric 

 is, properly, the matter producing the 

 sensation of heat. The words, however, 

 are often confounded, the term heat being 

 employed for both the cause and the 

 effect. 



1. Sensible or free caloric is that which 

 produces the sensation of heat, or affects 

 the thermometer. Insensible or latent 

 caloric is that portion which passes into 

 bodies during a change of form, without 

 elevating their temperature ; as into ice 

 at 32°, as it becomes water, and termed 

 caloric of fluidity ; or into water at 212°, 

 as it passes into vapour, and termed 

 caloric of vaporization. 



2. Specific caloric is the relative pro- 

 portion of caloric which any body retains 

 without the effects being sensible; and 

 the power of retention which a body pos- 

 sesses, is called its capacity for caloric. 

 The specific caloric of water is 23 times 

 as great as that of mercury; thus, if 

 equal weights of the former at 40°, and 

 of the latter at 160°, be mixed together, 

 the resulting temperature is 45°. 



CALORFFIC RAYS. Those rays 

 proceeding from the sun or any burning 

 body, which impart the sensation and 

 other effects of heat. 



