Report on the Solar Eclipse Expedition to Pulgaon. 59 



broad streamers on the limb subtended angles ranging from 

 10 to 30 at the centre of the sun's disc, and the radial 

 extension in three cases was estimated as being greater 

 than 12'. 



v) Two of the long streamers referred to in the last paragraph were 

 found to coincide roughly in position with marked broad 

 extensions in the direct photographs of the corona, viz., 

 that to the N.E. and that to the S.W. But the third long 

 streamer to the N. seems to have no connection with any- 

 obvious extension in the photographs. 



(vi) There was no marked " coronium " luminosity corresponding 

 either to the double-rayed extension in the N.W. quadrant 

 or to the broad extension in the S.E. quadrant. 



(vii) As far as it has been possible to pursue the investigation at 

 present, there has appeared no relation between the position 

 of the brighter patches of coronium and the prominences, 

 except perhaps near the three prominences in the N.W. 

 quadrant. 



VII. Polariscopic Observations. 

 By H. F. Newall. 



It was intended to devote any time that remained over, after pro- 

 viding for the three foregoing investigations during the eclipse, to 

 (i) a search for faint extensions of the corona with the aid of a 

 polariscope, or as an alternative (ii) a general investigation of the 

 nature of the polarisation-phenomena visible during an eclipse. It 

 was expected that results obtained in the latter investigation would 

 probably only be serviceable in suggesting methods of research for 

 future eclipses. 



The polariscope used consists of a Nicol prism with a Savart 

 plate attached in front of it. The field of view of the instrument is 

 lozenge-shaped after the manner of ISTicol prisms, the long axis being 

 29 long and the short axis 24. The width of the central band due 

 to the Savart plate was approximately 1 25' between the centres of 

 the first lateral dark bands, the centre being regarded as that part of 

 the dark band where the dusky red meets the steel blue. The plate 

 had been adjusted relatively to the Nicol prism, so that the bands 

 when visible were parallel to the principal plane of the Nicol, and 

 they were kept in this relative position throughout the observations. 

 The instrument was used without telescope or circles. 



Observations. When first the instrument was put to the eye, about 

 85 sees, after the beginning of totality, bands were visible over the 

 whole field of sky seen through the Nicol prism. Not only were the 

 alternations of brightness seen, but the colours of the bands appeared 



