LON 



LOO 



and then by correcting the altitudes for 

 parallax and refraction, two other zenith 

 distances may be had, which are correct, 

 and with these and the angle at the ze- 

 nith, a new triangle is constituted, of 

 which the oblique side is the correct dis- 

 tance. _ By comparing this distance with 

 those in the nautical almanack, the time 

 at Greenwich is obtained, and the differ- 

 ence between this and the time (observed 

 by an altitude or otherwise) at the ship, 

 gives the difference of longitude. Though 

 this computation with tables, which give 

 every tenth second, is not operose, it is 

 much abridged by the formulae given in 

 the said works. 



Time-pieces are likewise rendered so 

 perfect at present, that they afford the 

 most inestimable assistance to mariners. 

 See CHRONOMETER and HOROLOGY. Our 

 John Harrison, between the years 1726 

 and 1762, first vanquished the great diffi- 

 culty, and was rewarded with 20,0001. 

 from the English government. Very libe- 

 ral encouragement has since been given 

 to other artists, such as Arnold, Earn- 

 shaw, and others. 



LONGITUDE of motion, according to 

 some philosophers, is the distance which 

 the centre of any moving body runs 

 through, as it moves on in a right line. 



LONGITUDINAL, in general, denotes 

 something placed lengthwise : thus some 

 of the fibres of the vessels in the human 

 body are placed logitudinally, others trans- 

 versely, or across. 



LONGOMONTANUS (CHRISTIAN), a 

 learned astronomer, born in Denmark in 

 1562, in the village of Longomontam, 

 whence he took his name. Vossius, by 

 mistake, calls him Christopher. Being 

 the son of a poor man, a ploughman, he 

 was obliged to suffer, during his studies, 

 all the hardships to which he could be 

 exposed, dividing his time, like the phi- 

 losopher Cleanthes, between the cultiva- 

 tion of the earth, and the lessons he re- 

 ceived from the minister of the place. At 

 length, at fifteen years old, he stole away 

 from his family, and went to Wiburg, 

 where there was a college, in which he 

 spent eleven years; and though he was 

 obliged to earn his livelihood as he could, 

 his close application to study enabled 

 him to make a great progress in learn- 

 ing, particularly in the mathematical 

 sciences. 



From hence he went to Copenhagen ; 

 where the professors of that University 

 soon conceived a very high opinion of 

 him, and recommended him to the cele- 

 brated Tycho Brahe ; with whom Longo- 

 montanus lived eight years, and was of 



great service to him in his observations 

 and calculations. At length, being very 

 desirous of obtaining a professor's chair 

 in Denmark, Tycho Brahe consented with 

 some difficulty to his leaving him; giving 

 him a discharge filled with the highest 

 testimonies of his esteem, and furnishing 

 him with money for the expense of his 

 long journey from Germany, whither 

 Tycho had retired. 



He accordingly obtained a professor- 

 ship of mathematics in the University of 

 Copenhagen, in 1605 ; the duty of which 

 he discharged very worthily till his death, 

 which happened in 1647, at eighty-five 

 years of age. 



Longomontanus was author of several 

 works, which show great talents in mathe- 

 matics and astronomy. The most distin- 

 guished of them is his " Astronomica Da- 

 nica," first printed in quarto, 1621, and 

 afterwards in folio, in 1640, with augmen- 

 tations. He amused himself with endea- 

 vouring to square the circle, and pre- 

 tended that he had made the discovery 

 of it ; but our countryman, Dr. John Pell, 

 attacked him warmly on the subject, and 

 proved that he was mistaken. It is re- 

 markable, that, obscure as his village and 

 father were, he contrived to dignify and 

 eternize them both ; for he took his name 

 from his village, and in the title-page 

 to some of his works, he wrote himself 

 Christianus Longomontanus Severini fi- 

 lius;;his father's name being Severin or 

 Severinus. 



LONICERA, in botany, honeysuckle^ 

 named from A. Lonicer, a genus of the 

 Pentandria Monogynia class and order. 

 Natural order of Aggregate. Caprifolia, 

 Jussieu. Essential character : corolla one- 

 petalled, irregular; berry many-seeded, 

 two-celled, inferior. There are nineteen 

 species, of which L. grata, ever-green 

 honeysuckle, is the most beautiful : it 

 grows naturally in North America : it has 

 strong branches, covered with a purple 

 bark, which are ornamented with lucid 

 green leaves, embracing the stalks, and 

 continuing their verdure all the year ; 

 the flowers are produced in whorled 

 bunches at tke end of the branches ; 

 there are frequently two, and sometimes 

 three, of these bunches rising one out 

 of the other ; they are of a bright red on 

 their outside, and yellow within, of a 

 strong aromatic flavour; it begins to 

 flower in June, and there is a constant 

 succession of flowers till the frost puts an 

 end to them. 



LOO, or lanter-loo, a game at cards. 

 See LAXTER-LOO. 

 LOOP, in the sea-language, is a term 



