SUR I,A COMÈTE 1901 I. 459 



Wlien uext seeu with the 10-iucli ou April 26 the cornet was very 

 faint, but the uucleus did uot seem smaller. Ou April 27 1 could uot find 

 the cornet, nor did I see it again until the evening of May 3, wlien the tail 

 was quite altered. It now consisted of two uearly equal portions streaming 

 from each side of the nucleus, not very unlilie De la Rue's drawings of 

 the cornet of 1861, but the nucleus was round ^). 



Evening Observations of Cornet, 1901 May 3— May 12. Mr. Lunt's 

 description. — The most reraarkable feature of the cornet, viz. the long 

 faint precediug^) tail did uot become visible until the cornet had emerged 

 from the strong twiiight. It was first seen ou the evening of Friday, May 3, 

 as a faiut ray, scarcely distinguishable, springing from the head at an angle 

 of about 40° to the main tail. This faint tail appeared on two photographs 

 taken with a portrait lens the same evening. Ou the two following nights 

 however, as the cornet receded further from the Sun and became visible 

 against a darker sky, it was a most conspicuous feature. Ou the evening 

 of Monday, May 6, the faint tail was seen to be quite four times as long 

 as the main tail and fiilly 30° in length, but fading away so gradually that 

 it was difficnlt to place any exact limit to it. At this time the cornet attain- 

 ed its maximum splendour as a naked-eye object. With an exposure of 

 25 minutes a portrait lens showed not only the main faint tail, but two 

 still fainter rays between it and the bright tail, clearly discernible in the 

 lantern slide sent herewith. 



The space on each side of the faint rays was filled with faint light, 

 and the darker space between them showed clearly by contrast, althoug the 

 two faint rays themselves were not so well marked to the eye as they ap- 

 pear in the photograph. 



In the accompanging drawing I hâve eudeavoured to represent the 

 dimensions and most striking features of the comet as revealed both by eye 

 observations and photographs. The position is that of the evening of Sun- 

 day, May 12 (PI. II, 12 mai), by which time the comet had become in- 

 trinsically much fainter, although as seen in a still darker sky it was yet 

 a magnificent object. 



The preceding side of the main tail was not then so markedly strenger 

 than the following side as previously, but the tail still streamed off from 

 each side of the nucleus in rays brighter than the space between them, 

 which was filled with fainter light. The faint preceding tail was still fully 

 25° long, and reached, as shown in the drawing, as far as 8 Leporis. The 



1) La comète 1861 avait plusieurs enveloppes paraboliques autour du noyau. 



2) Précédant dans le mouement diurne et suivant dans le mouvement orbital. 



Фпз.-Мат. стр. 363. g 



