1'n.f. H. H. Turner an.l Mr. II. K. Xewall. 



The ninth Savart polariscope was mounted in a turning tube with 

 pointer and circle complete, on a lioard which was screwed to an 

 inclined block on the western doorpost of the hut which contained my 

 spectroscopic apparatus. It was pointed towards the corona, and was 

 in fact the visual Savart used l>y myself in the way described in the 

 previous section (p. 363) for determining the position of the plane of 

 polarisation of the light from the sky in the immediate neigh bourhood 

 of the corona, so that the camera Savart could l>e adjusted accordingly. 

 The polariscope had been left in position with the bands horizontal 

 and the pointer at 90". Six seconds after the beginning of totality I 

 left the spectroscope and looked through the polariscope. The eclipsed 

 sun was slightly (perhaps 5) to the north of the centre of the field of 

 the Savart. The Iwnds were seen fairly strong over the whole field 

 of view, the central band being black. The Savart was then turned 

 counter-clockwise, until the bands were extinguished. The reading 

 was found to be 9 on the scale arranged to correspond with that on 

 the large Savart in Professor Turner's hut. This reading showed 

 that the plane of polarisation of the sky in front of the corona was 

 inclined at an angle 4" to the vertical read counter-clockwise from the 

 vertex. (There is possibly a zero error ; it has not yet been deter- 

 mined.) When the atmospheric bands were extinguished faint traces 

 of bands were seen over the corona, but much less strong than in the 

 Indian eclipse. 



I examined the polarisation of the sky in the zenith about 10 seconds 

 after the end of totality, and found that the plane of polarisation 

 passed through the sun. 



Mrs. Newall undertook the charge of the eight other polariscope*, 

 which were arranged as described above, and her programme for the 

 eclipse was to turn each instrument, so that the Savart bands dis- 

 appeared, paying attention to the direction of turning as follows : 

 If the band system had a white central band the polariscope was to be 

 turned clockwise. If the system had a black central band it was to 

 be turned counter-clockwise. The instruments were then to be left 

 untouched, and the positions of the pointers were to be written down 

 at leisure after the eclipse. Mrs. Newall devoted herself very dili- 

 gently to setting the instruments under very varied conditions on the 

 days preceding the eclipse, and so expert did she become that she was 

 able to make the necessary settings of all eight polariscopes in about 

 42 seconds. If the polarisation was weak, about 50 seconds were 

 needed. In the following table, taken at random from her note- 

 book, the figures in the upper line are the readings of the pointers of 

 the various polariscopes when the settings were made in a leisurely 

 manner ; those in the lower line are the readings when the settings 

 were made " racing." " Hor." refers to the horizontal polariscope : 

 " 30" " to that which points upwards : 



