11 



awarded the Smith Gold Medal of the American National Academy 

 of Sciences, in recognition of his original work. In this country 

 he was elected a Foreign Member of the Royal Society, of the 

 Royal Astronomical Society, and of the Royal Society of Edinburgh. 



The first of his papers seems to have been published in 1857, and 

 the last, " On the Relation of the Plane of Jupiter's Orbit to the 

 Mean Plane of 401 Minor Planets," in 1895. Between these dates 

 he published a long series of papers usually from two to four each 

 year covering a variety of subjects in mathematics, insurances, and 

 especially in that branch of astronomy which relates to meteors and 

 comets. These intimately connected phenomena early fixed his 

 attention. His first paper in reference to them was published in 

 1860, and a continuous succession, nearly fifty in all, have been the 

 result of his studies in this department of astronomy, and have con- 

 tributed largely to the immense advance which the astronomy of 

 meteors has made within the last forty years. 



Two memoirs may be selected to illustrate how much modern 

 science owes to Professor Newton's industry and clear insight. The 

 first of these is his great memoir entitled " The Original Accounts of 

 the Displays in former times of the November Star-shower : together 

 with a Determination of the length of its Cycle, its Annual Period, 

 and the probable Orbit of the Group of Bodies round the Sun." 

 This memoir is published in the 'American Journal of Science ' (' Sil- 

 liman's Journal'), vols. 37 and 38 (1864). In it Professor Newton 

 makes use of the collections of ancient records of . star-showers 

 which had been brought together chiefly by the great industry of 

 French antiquarians and French astronomers. From these records 

 Professor Newton traces out all which refer to former visits to the 

 earth of that great swarm -of small bodies which are now known as 

 Leonids, but which, when first observed, radiated from the constella- 

 tion Cancer. In each case he cites the actual words of the original 

 records, of which there are usually several referring to each shower ; 

 and by a careful scrutiny of these he is able to fix, in many 

 instances with certainty, in others with more or less probability, 

 the actual date on which each shower occurred, and even in some 

 cases the hours during which it lasted. He thus discovered that we 

 possess records of thirteen showers of these meteors, of which 

 the earliest was in A.D. 902, and the last (at the time when he 

 wrote this memoir) was in 1833. To these we have now to add 

 the two great displays witnessed from Europe in 1866, and from 

 America in 1867. 



By this careful scrutiny Professor Newton discovered several im- 

 portant facts that the main swarm returns to the earth at intervals 

 of 33'25 years ; that on each return the earth encounters the dense 

 part of the swarm in two consecutive years ; that the date of the 



