5A6 ' PHILOSOPHICAL TRANSACTIONS. [aNNO 16S2, 



j4n Account of another small Treatise written in High-Dutch, and printed at 

 Bazily Anno 168I. Containing a Neiv Theory about the Comets, invented by 

 James Bernouilli,* the Title whereof is thus expressed : Anew Introduction, show- 

 ing hoiv the Motions of Comets may be reduced to some certain and Geometrical 

 Rules, so that their appearance may be predicted. Philos. Collect. N° 7, p. 199. 

 Before explaining his theory, he thinks it proper to say something of the 

 original cause of comets, of their course and motion, of their place and tail. 



What concerns their principal or original cause, he says, that that old opi- 

 nion which supposes them to be a collection of vapours and exhalations put into 

 a flame by the uppermost part of the air, is scarcely worth any consideration : 

 for if the comets by such an inflammation should have their light of themselves, 

 there could be given no reason why the tail should always be seen in opposition 

 to the sun ; and moreover if the whole earth should be resolved into vapours, 

 there would not be enough to form only the tail of such a comet. Descartes's 

 opinion, he says, is strange enough : for according to this hypothesis, the sun 

 or our earth might after sometime be transformed into a comet, as some have 

 endeavoured to prove out of the solar spots. The author's own opinion is, that 

 comets are like other stars or planets, perpetual bodies, which have their certain 



* James Bernoulli, a celebrated mathematician of the I7th century, and professor of mathematics 

 at Basil, was born at that town l654. His father intending him for the church, placed him in that 

 university to study divinity. But his inclination leading him powerfully to astronomy and mathematics, 

 he soon made a considerable progress in those sciences, witliout a preceptor, and almost without books, 

 and even as it were by stealth; a circumstance which led him to adopt for his device. Phaeton driving 

 the chariot of the sun, with this motto, " Invito patre sidera verso," I traverse the stars against my 

 father's will. From \676 he spent some years in travels in Germany, France, Holland, England, &c. 

 from whence he returned to his native country in l682, where he exhibited a course of experiments 

 in natural philosophy and mechanics, consisting of various new discoveries. The same year he pub- 

 lished his Essay on a new System of Comets, as above, and the year following his Dissertation on the 

 Weight of the Air. About l684 M. Leibnitz published in the Leipsic Acts, some essays on the new 

 Calculus Differentialis, but without discovering the method of it, Bernoulli, on explaining it, received 

 great applause from that philosopher, who declared tlie invention belonged as much to Bernoulli as to 

 himself. In this matter, and in that of Series, however, it is probable, he had derived some know- 

 ledge by his communications with men of science when in England. In l687, Bernoulli became pro- 

 fessor of mathematics in the university of Basil, where he died in 1705, in the 51st year of his age, 

 by a disorder arising from his close and intense application to study. Many of his compositions were 

 published in the Memoirs of the Academies of Paris, Berlin, Leipsic, &c. His works were collected 

 and published at Geneva 1744, in 2 vols. 4to. j but with the unaccountable omission of his posthumous 

 work, De Arte Conjedandi, one of his most ingenious labours, and published in 1713. James Ber- 

 noulli had an excellent genius for invention and elegant simplicity. He introduced his younger brother 

 John into his own favourite sciences, who lived to a great age, and became equally celebrated with 

 "himself, and indeed often held very rude and vexatious contention with him for the mastery in those 

 sciences. Their descendants have also to this day continued to pursue the same illustrious career in 

 the mathematical sciences ; resembling in that respect very much the celebrated race of the Gregories 

 in this country. 



