e A i 



Gallic, which only a small impression Was published, he 

 v ' gave the positions of 397 principal stars, which he 

 had determined with the utmost exactness, by means 

 of two instruments of six feet radius, at the observa- 

 tory of the Mazarine College. This catalogue was 

 the result of nearly ten years labour, and cost him 

 more trouble than if he had determined the positions 

 of 4000 in the common manner, f It was followed 

 by another, containing the right ascension and de- 

 clination of 1942 southern stars, selected from the 

 10,000 which he observed at the Cape.J The 

 right ascension and declinations of the other 8000 

 have not yet been calculated, but all the observations 

 were published by Maraldi in 1763, in a work en- 

 titled Ccelwm Australe Stelliferum. Between Septem- 

 ber 1760 and March 1762, La Caille determined the 

 positions of 515 zodiacal stars; but in the midst of 

 these observations, he fell a victim to his ardour 

 for astronomy. In 176'0 he had been attacked with 

 a severe fit of the gout ; but though it did not inter 

 rupt his observations, his health began gradually to 

 decline, and being seized with a malignant fever 

 on the 15th of March, he died on the 21st of March 

 1762. M. Bailly finished the calculations which 

 La Caille had begun, and published the catalogue 

 of 515 zodiacal stars, at the beginning of the ephe- 

 merides for 1765 1774, which had been calculated 

 by La Caille. This catalogue is also incorporated 

 with the catalogue in our article on ASTRONOMY. 

 It has been lately republished by Mr Vince in his 

 Complete System of Astronomy, vol. ii. p. 513. 



In addition to these valuable catalogues, the science 

 of astronomy owes many other obligations to La Caille. 

 After comparing the numerous observations which 

 he made on the parallaxes of the planets, with the ob- 

 servations of Bradley, Zanotti, Cassini, Gentil, War- 

 gentin, Strommer, and Scheumark, he found that 

 26".8, the mean of 27 results, was the horizontal pa- 

 rallax of Mars on the 14th September 1751, the day 

 of his opposition to the sun ; and that the horizontal 

 parallax of the sun was 10^". His memoir on Astro- 

 nomical refractions, published in the Memoirs of the 

 Academy for 1755, contains much valuable informa- 

 tion on that difficult subject. It is founded on the 

 comparison of the distances of 160 stars from the ze- 

 niths of Paris and the Cape, each of which were ob- 

 served at least six times with very good instruments. 

 Beside the works which we have mentioned, La 

 Caille published the Memoirs of Father Feuille at 

 the Canary Isles ; the Journal of M. de Chazelle's 

 Voyage to the Levant ; the Astronomical observations 

 f William, Landgrave of Hesse, which the Duke 

 de Laval had found at Cassel ; and a new edition of 

 Bouguer's Essai d'Optique sur la Gradation de la 

 Lumiere. which appeared in 17(iO. 



La Caille was elected a member of the Royal So- 

 cieties of London and Gottingen, and of the Acade- 

 mies of Petersburgh, Berlin, Stockholm, and Bo- 

 logna ; and such was his industry and labour, that 

 La Lande maintains that he made more observations 



C A I 



and calculations, than all the. astronomers together 

 who lived at the same time with himself. La 

 Caille had sketched out the plan of an extensive 

 work, to be entitled, ' The History of Astronomy 

 through all ages, with a comparison of tae ancient 

 and modern observations, and the construction and 

 use of the instruments employed in making them ;" 

 but he did not live to make any progress in the com- 

 position of it. Science might have long regtetted 

 this unfortunate event, had not the celebrated Bailly" 

 executed the same plan with such brilliant. success. 



The memoirs published by La Caille will be found 

 in the Memoirs of the Academy for 1741, 1742, 

 1743, ]"44, 1745, 1746, 1747, 1748, 1749, 1750, 

 1751, 1752, 1753, 1754, 1755, 1756, 1757, 1758, 

 1759, 1760, 1761, 1763. See the Histoire dfL'A- 

 cademie, 1762; Connoissance des Mouvemens Celes- 

 tes, pour 1767 ; and the Journal Historique du 

 Voyage fait au Cap de Bonne Esperance, par M. 

 De la Caille, published at Paris in 1763 by M. Car- 

 lier. (0) 



CAIRN, a heap of stones thrown together in a 

 conical form. Cairns seem to differ from barrows, 

 only in regard to the materials of which they are 

 composed : they both - seem to have been designed 

 for the same purposes ; and accidental circumstances 

 directed the one to be constructed of stones, and 

 the other of accumulated earth. In Scotland and 

 Wales, cairns are more common, because the ma- 

 terials are every where to be found in abundance. 

 In England, barro\vs are more frequent, because 

 stones are not so easily procured for the construction 

 of these monuments. In Egypt, the two forms 

 are sometimes found conjoined, as when a conical 

 mound of earth is surmounted by a pyramid of 

 bricks. 



It is in vain that we attempt to trace the history 

 of cairns, or to deduce their origin from any parti- 

 cular nation ; they evidently originate in principles 

 common to human nature, and were the first rude 

 monuments of events which men were desirous to 

 commemorate. Wherever we read of a pillar, or ,a 

 stone set up as a memorial, we see the origin of the 

 cairn, and the principle which gave rise to its con- 

 struction : Gen. xxxi. 46 ; Josh. iv. 5. The dura- 

 bility of the substances, of which these monuments 

 were composed, recommended them as memorials to 

 more polished ages, and the splendid pillar and stu- 

 pendous pyramid are only improvements and exten- 

 sions of this simple structure. 



From this view of the subject, it is evident that 

 we do not mean to confine the uses of cairns, either 

 to the purposes of religion or sepulture : they seem 

 to have been applied to any event which appeared 

 particularly worthy of commemoralion. The Israel- 

 ites raised a great heap of stones on the body of A- 

 chan, as a monument of perpetual infamy, Josh. vii. 

 26 ; and they also raised a heap of stones to celebrate 

 their miraculous passage over the river Jordan. lu 

 the same manner, cairns are raised in Scotland to this 



Cairfi, 



f This catalogue is incorporated with the general catalogue of the fixed stars, which we have given in the article ASTRO- 

 NOMY, vol. ii. p. 745. 



$ This catalog;; was published in the Memoirs of the French Academy for 1752, and has been republished in the Tables cfe 

 Berlin, tom.'iii. p. 183. 



Introduction to th* Ephemerides de 1765 1 774-, p. *. 



