The daily morning journal and courier., 1896-07-14
4 COMETS TRAVELS.
some interesting Facts About the Most
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 made through the official center for such news in this country, Messrs Chandler and Ritchie of Boston, that Brooks' periodical comet has been de- tected on it's return to the sun by Ja- Vello and assistant at the observatory at Nice. This comet, while not even visible without telescope, is the most interesting object of its kind. This in- terest exists not only among astrono- mers but among those intelligent per- sons who are little familiar with the popular features of astronomy. MT. wv. R. Brooks is an amateur astrono- mer at Geneva, N. r., who for quite a number of years occupied his spare evenings searching for comets. In nndlng these he was very successful and is surpassed only by Dr. Lewis Swift in point of numbers of such ob- 5ects seen for the first time. In July, 1oS9, he found this comet, the fifth one discovered during that year, a faint patch of light, which seemed to have no particular interest to people in gem eral. But the earliest orbits computed, those by Drs. Chandler and Searle, gave evidence that the object was nov ang in an elliptical orbit, the period of revolution about the sun being seven Or eight years Of course astronomers at once pricked up their ears and pointed their telescopes towards the object; for when a comet is known to be periodical, every effort is made to nhCprxya 60 haf oc tn r, orbit as possible may be computed, and its motions before and after it's current apparition be determined as closely as possible. Upon such work as this is dependent all that we have learned about these travellers of the skies, which come we know not whence, and go away again, many of them, we anow not whither.
 The reader will at once inquire, of course, What can there be about his Insignificant comet, which we cannot even see unless we have a telescope, to make it so interesting to us?" There are several reasons for this: first, 1t Is possible that it is indeed LexelPs com ct, which was lost very many years ago; second, it is the only comet that to our knowledge has been entangled in the satellites of the great planet Jupi- ter; and third, 1t is one of the few com cts which we know to be groups instead of individuals, having several members which move through space in almost the same path, and are together in the close company in the same parts of their orbits. One of these reasons alone would be a delight to the astron- bmer, but to have them united in the same object is exceedingly noteworthy
 The Brooks comet is one of the Jupi- ter group of comets. These are little family of comets which have beer made members of our company through the attractive influence of Jupiter, the s'bu1ly of the solar system," as he has been appropriately termed The way ir which we acquire comets Is this: From out in space these little masses of gas come within the attraction of the sun and about our central luminary they move in a regular orbit, usually the geometrical figure called the hyperbo la, and having passed the sun they go out again into space in almost z straight line never to return. The sur has disturbed their motion through space by altering it's direction. But Ii 1t should happen that after the come has decided to swing partners" witt the sun, there is one of the large plan cts near it's track, this planet will ex ercise it's attraction, and on it's own ac count make some changes in the patl ], of the traveller. Mathematicians un derstand the laws which regulate thi disturbance, and it is usually the cas- that the disturbed comet is forced int an orbit which is an ellipse, the sun be ing at one of it's foci and the extremit. of the orbit away from the sun extend ing out to near the place where the dis turbance was effected. Jupiter is al enormous planet, more than three hun dred times as heavy as the earth, an' 1t moves in it's orbit at very fast rat for so large a planet. The region tha ds patrolled by it, therefore, Is yer. large, and it's attraction has brought il as, members of our system more thai thirty comets, which for the present a least are moving in orbits about tn sun, reporting to that luminary by
 close approach every few years, an will continue to do so until they ar Iissipated, or until coming again i the vicinity of Jupiter, they are or dered away on some other errand. Flo 1t should be remembered, the condition under which the path of the comet wa changed from parabola to an clips may at some time be exactly reversed and the comet may be set free agai after centuries of captivity by 9 per turbation from the very planet tha caught it.
 Very soon after the discovery b Brooks of the fifth comet of 1883, Whe observations enough had been secure by astronomers, Dr. $. c. Chandle computed the track over which tn comet had come before it was dlscoV cred. to see if he could find out whe had been its past history. In doin 4bis he came across some curious fac, which inclined him to the bellef ths this comet was truly the lost Lexel which in the interim of fifty years ha
 met with variety of fortunes ( 1Y1TIEudN R kTsN