SCIENCE-GOSSIP. 



321 



When the eclipse came, however, unforeseen 

 disturbances arose, so that M. Kostinsky only 

 managed to obtain four photographs. Prince 

 Galitzine obtained four with his camera, but failed 

 with the spectrum, one reason for the failure being 

 that his instrument had too great a dispersive 

 power. 



There was a strong wind until after the time of 

 the first contact, but after the second there was 

 almost a calm. 



The totality caused such a profound impression 

 that it was difficult for them to recall themselves 

 to the work. The floating cirrus clouds and 

 the shortness of the time prevented the proposed 

 observations around the sun. But Mercury, 

 Venus, Jupiter and Regulus were seen — as also 

 was the^case at Bodo. According to M. Backlund, 

 it was so dark that one could hardly see to write 

 n the journal — darker than in full moonlight. In 



especially when sketching the corona. It was as 

 dark as at two hours after sunset at Odessa." 



M. Kostinsky writes that " It was as light as full 

 moon, but the tint was peculiar — orange ; the 

 colour of the neighbouring clouds was of the same 

 tint. I only looked at the corona for a few 

 seconds." 



Owing to the shortness of the time M. Hansky's 

 drawing was not a success. By the end of the 

 eclipse clouds again covered the sky. But, this 

 notwithstanding, several other photographs of the 

 sun were made during the day. The diagram 

 accompanying this paper (fig. i) is a resultant one, 

 drawn after the return to Poulkova, and bringing 

 in all the details visible on each of the photographs 

 and calling attention to several minute details 

 which might easily be overlooked if the photographs 

 were alone consulted. 



The first photograph taken with the equatorial 



Fig. 3.— Total Eclipse of the Sun, August qth, iS 



the east the atmosphere appeared bluish, and in 

 the south of an orange tint. Seven seconds before 

 the commencement of totality the red light of the 

 chromosphere (i) was very intense. The corona, 

 which presented a considerable expanse, was of an 

 orange colour. 



M. Hansky says, "The colour of the corona 

 seemed to me bluish. I did not see the 

 prominences. The rays were very intense on the 

 left with the naked eye. Little detail with the 

 telescope ; more with the unaided eye. The ray 

 turned towards the zenith stretched for at least one 

 or one and a-half diameters of the sun. The others 

 were not longer than a-half the diameter, or even 

 less. A lantern had to be used during totality, 



(') The chromosphere is the gaseous envelope which 

 surrounds the sun completely to a depth varying from 2,000 

 to 6,000 miles. This gives bright lines in its spectrum, where 

 dark lines are seen in the spectrum of the sun itself. 



on a plate by Thomas, had three seconds exposure, 

 and the development was carried on until there 

 were certainly no more minutas to be brought out, 

 a method adopted with each plate. It showed 

 very much detail ; but the best photograph was 

 that taken next. " No. 2. Exposure = ten seconds. 

 Schleussner plate. The reproduction (fig. 2) is a 

 little fogged. The corona is of very considerable 

 extent, the principal ray reaching to the edge of 

 the field, and even probably extends beyond it. 

 The details of the corona in its outer portions 

 are very well shown. One can also see all the 

 prominences, but somewhat distorted on account 

 of the slight movement of the image in the direction 

 of the parallel " — in other words from east to 

 west. " It was evident that the clockwork move- 

 ment was not entirely uniform." These two plates 

 were the most interesting and important taken, 

 from the amount of detail shown. 



N 2 



