APRIL 9, 1903 



NA TURE 



535 



LETTERS TO THE EDITOR. 



[The Editor does not hold himself responsible for opinions 

 expressed by liis correspondents. Neither eon be undertake 

 to return, or to correspond with the writers of, rejected 

 manuscripts intended for this or any other part of Nature. 

 No notice is taken uf anonymous communications.] 



The Quadrantids, 1903— A Coincidence. 



A friend of an astronomical turn of mind called a few 

 evenings ago and related to me the following : — 



" At 5 p.m. on the first Saturday in January, i.e. January 

 3, I was on a hill outside Bangor, Co. Down, looking west- 

 wards, when a large bright meteor, magnitude = Jupiter, 

 appeared above the south-western horizon, and rose slowly 

 and perpendicularly until it attained an altitude of ^about 

 30 degrees : duration, two or three seconds : no sound or 

 explosion, but a fine sight in the strong moon or twilight." 



Observers will notice the agreement of the date of this 

 meteor with that of the Quadrantids, and one is tempted to 

 ask if it could be a member of that system, drawn out of 

 its course, or was it an ordinary slow, direct-motion, fireball 

 from the west? My informant says, judging from the 

 position of Jupiter and the moon at the time, that its path 

 lay in the ecliptic. 



I may remark in connection with this subject that on or 

 about the date of maximum of some of the larger showers, I 

 have frequently noticed, and sometimes had reported to me, 

 the observances of slow, irregular meteors which, although 

 obviously connected in some way with the shower under 

 observation, were yet quite unconformable as to the radiant ; 

 and I came to the conclusion that they were meteors which 

 had been trapped or captured at former returns, and were 

 then members of those sun-earth systems referred to by 

 M. Schulhof in his papers " Sur les Etoiles Filantes " (Bull. 

 Astron., March-September, 1894, pp. 64, 65). 



The question may not have hitherto received the attention 

 it deserves, but I leave it to those more competent to judge. 

 The outside planets control their cometary systems and 

 swarms. Why not the earth on a smaller scale? 



My own observations of the shower this year were not at 

 all satisfactory, and were briefly as follows : — 



January 2. — 12-1 a.m., Quadrantids nil. 



January 3. — Overcast. 



January 4. — 2.30-3 a.m., Quadrantids 15. 



The display was evidently closing when I took up my 

 watch. I, however, placed the hourly rate as high as sixty 

 for the short time it lasted. Several of the meteors were 

 fine, bright, steel-like flashes, straight from the radiant 

 through the zenith, in marked contrast to others, which were 

 of a much slower and sporadic-like character. 



YV. 11. Milligan. 



26 Cooke Street, Belfast, March 23. 



The phenomenon referred to in his letter, by Mr. Milligan, 

 that the principal star-showers of the year are in general 

 accompanied simultaneously, or nearly so, by a somewhat 

 more than ordinary abundance of shooting-stars from centres 

 not very far distant from that of the principal display, has 

 long been observed, and has indeed received an elaborate 

 amount of attentive study, as a pretty clearly distinguishable 

 character of several of those showers ; but it can hardly be 

 said that observations of those dispersed contemporaneous 

 meteor-flights have yet been made with such satisfactory 

 exactness as either to assign them all to real centres, or to 

 say with certainty how many of them are stragglers from 

 the main and from the neighbouring shower-sources. In 

 the present imperfection of our knowledge of the pheno- 

 menon's real features, no recourse, it may be feared, can yet 

 be had with any prospect of successful issues to hypo- 

 thetically ventured explanations of these, either closely 

 grouped together, or else, by perturbative attractions, errati- 

 cally scattered and deflected contemporaneous meteor- 

 systems. 



The Ouadrantid shower appears to have reached its 

 maximum this year in the evening and night of January 3 ; 

 for in watches of about two hours towards midnight on 

 that date, rather rapid hourly rates of appearance of the 

 Quadrantids were noted both bv Mr. T. H. Astburv, at 



Wallingford, and by Mr. A. King, at Leicester, some of the 

 meteors recorded being very bright ones ;' and this date 

 of its greatest brightness was thus confirmed by the consider- 

 able intensity of the shower observed at a later hour on the 

 same night by Mr. Milligan in Belfast. Much clouded sky, 

 and rain prevailed on that night at Slough, but in a clear 

 interval of about 1 hour, between i2h. 35m. and I3h. 50m., 

 nine meteors were mapped, of which four or five diverged 

 from Quadrans. During a watch of nearly 5 hours on 

 the preceding night of January 2-3, from I2h. 10m. to i-h. 

 5m., with continually clear sky, = thirty-four meteors were 

 mapped and three or four more were seen, appearing at a 

 steady rate of seven or eight per hour. Of the mapped 

 meteors five were Quadrantids, three of them equal to or 

 brighter than first magnitude stars ; all seen in the last ij 

 hours, and none in the first 35 hours of the watch, denoting 

 apparently a distinct beginning of the shower at about 

 3h. 30m. a.m. on the morning of January 3. 



The radiant-point of four Quadrantid tracks was well 

 marked at 233°+S4° ; but with five more on January 3, alt 

 from about 225° 4-49°, the mean of the nine paths was at 

 229° + 52°. At i6h. 38m. on January 2, a Sirius-like brief 

 white flash was quite stationary for half a second, ,11 

 228°+59°. A mean place of the radiant-point at 228!°+- 

 52J was also obtained by Mr. W. E. Besley, at Clapham, 

 from six Ouadrantid tracks among seventeen to twenty 

 meteors mapped and glimpsed in a watch, with clear sky 

 from nh. to 13!). 20m., on the night of January 3. Evident 

 signs of radiation by three or four meteors from each point 

 were also noted here from i8o + 55° (5 Ursa? Majorids, II.), 

 258° + 44° (/3 Draconids), and 235° + 36° B Coronids), round 

 the Caput-Bootid, or Ouadrantid radiant-region, and notably 

 also from one more distant source (e Craterids), at about 

 160° — 8° (five meteors), and from a weaker one at about 

 2io° + d°, Mons-Mcenalids or (15) Bdotids. 



The large meteor described by Mr. Milligan as having 

 been seen at Bangor, Co. Down, at 5)1. p.m. on January 3, 

 shooting upwards in the S.W. nearly along the path of the 

 ecliptic, or from some radiant-point near /3 Aquarii in the 

 sunset vicinity, was indeed, as early evening fireballs some- 

 times are, directed from an exceptionally far western 

 quarter. But as its radiant-source was at least 100° off 

 from that of the Quadrantids, then near the N.W. horizon, 

 it could only, surely, be in a course of countless ages that we 

 might suppose it to have become so widely divergent in its 

 route from the star-shower's path-direction, since this would 

 need many times repeated, always like-acting close 

 approaches to the earth, with the only small deflecting 

 actions in each of them which the earth by its attraction 

 would be able to exert on the direction of its motion. 



A. S. Hersciiel. 



Observatory House, Slough, March 28. 



Analogue to the Action of Radium. 



Is not the generation of radiant energy by radium analo- 

 gous to the humming of telegraph wires and poles? In 

 each case the emission of energy is a response to surround- 

 ing disturbances which elicit no response from bodies in 

 general. The disturbances from which the energy is drawn 

 are irregular movements, of the air in the one case, and of 



1 From Mr. King's description in the English Mechanic of February 6, 

 1903 (vol. lxxvi. p. 544), of his view of 8 to 10 Quadrantids seen and 

 mapped in 45m. of cloudless, only slightly hazy sky, after qh. (none 

 having appeared in the previous hour, from 8h. to oh., of equally clear 

 watch), their rate of appearance then, allowing for haze, and for time 

 spent in registration, was about 17 to 23 fer hour, and they were "coming; 

 as frequently as the Perseids in the early hours of their maximum 

 dates." The eight mapped flights (of which one was as bright as Sirius, 

 and five were equal to or brighter than second magnitude stars) showed a 

 radiant-point at 228° 4- 52°. Mr. Astbury saw 19 Quadrantids during a 

 watch of rh. 45m. between 6h. and ioh. 30m. The thirteen mapped paths 

 gave "two good centres, one at 23r -f- 54 (5 Quadrantids) and a second at 

 225° 4- 53 (5 Quadrantids)." The three remaining "fell near, but not on, 

 these centres" 



2 Three or four flashes of lightning were noticed on that night, as also 

 happened on that date in the bright return of the Quadrantid shower in 

 1900. In the clear watch of s£ hours kept at Slough on the latter night, 

 considerably more meteors (35 together) than the 28 observed well centred 

 paths from Quadrans. appeared to diverge from the following five positions, 

 which, with the 8 Ursid centre seen this year, were distributed round the 

 January shower's radiant region near the Huntsman s head pretty closely, 

 and pretty evenly in all directions, thus : — 216° + 34' (p Bootids, 8 meteors)* 

 243 + 20° (£ Coronids, 8 meteors), 257° + 44° (/S Draconids, 7 meteors), 

 260 4- 65° (£ Draconids, 7 meteors), and 242 -j- 75 (y Ursse Minorids, 

 5 meteors). 



NO. 1745, VOL. 67] 



