58 Capt. E. H. Hills and Mr. H. F. Newall. 



The instrument was mounted so that the telescope was parallel to 

 the earth's axis and pointed towards the north pole. The grating 

 was used in a manner analogous to that in which the mirror of a 

 polar heliostat is used. The light of the corona was incident on the 

 grating at an angle of about 57, and diffracted beam utilised in the 

 telescope left the grating at an angle of about 13. In this posi- 

 tion of the grating, the green of the second order was used, and the 

 magnifying power of the grating was a little greater than ^, so that 

 the distorted coronal ring was an ellipse, in which the major axis 

 was about twice as great as the minor axis ; the minor axis was 

 parallel to the length of the spectrum and perpendicular to the 

 direction of daily motion. No clockwork was used, but a slow 

 motion of a very simple construction was provided and found to 

 work perfectly satisfactorily. The observations were begun 6 

 seconds after the beginning of totality, and were completed in about 

 70 seconds. 



Results. The coronal ring was seen in the spectrum of the second 

 order with great distinctness and with such brilliancy as to leave no 

 doubt that it could have been photographed. 



None of the fine radial structure of the corona could be seen, 

 though it was especially looked for ; but broad patches of light were 

 clearly visible in different positions round the ring. 



A drawing of the brighter extensions was made during the eclipse, 

 the observer (N.) keeping himself intentionally in ignorance of the 

 orientation of the image seen in the eye-piece until after the observa- 

 tions were completed so as to avoid bias. A preliminary comparison 

 of the drawing with the direct photographs of the corona has been 

 made, and the following general statements will probably not require 

 much revision on a closer comparison : 



(i) There appeared to be glowing " Coronium " (assuming that the 

 radiation of wave-length 53 16' 9 is rightly attributed to 

 an element " coroiiium ") at all points round the sun's limb 

 extending radially to distances estimated as ranging bet ween 

 4' and 14'. 



(ii) The luminosity was not uniform round the limb, but in no 

 position was it entirely absent. 



(iii) No fine radial streamers comparable with those seen near the 

 poles of the sun in ordinary direct photographs of the 

 corona were observed) though this fine structure was 

 specially looked for* 



(iv) In certain positions round the limb patches of increased 

 luminosity were seen ; in all, seven patches were noted ; in 

 several cases the extension was considerably greater in a 

 radial direction than in a tangential. The bases of the 



