VOYAGE TO ALGERIA ^ 16T 



I was provided with a telescope of admirable defini- 

 tion, mounted, adjusted, packed, and most liberally placed 

 at my disposal by Mr. Warren De La Rue. The telescope 

 grasped the whole of the sun, and a considerable portion 

 of the space surrounding it. But it would not take in 

 the extreme limits of the corona. For this I had lashed 

 on to the large telescope a light but powerful instrument, 

 constructed by Ross, and lent to me by Mr. Huggins. 

 I was also furnished with an excellent binocular by Mr, 

 Dallmeyer. In fact, no man could have been more effi- 

 ciently supported. It required a strict parcelling out of 

 the interval of totality to embrace in it the entire series 

 of observations. These, while the sun remained visible, 

 were to be made with an unsilvered diagonal eye-piece, 

 which reflected but a small fraction of the sun's light, this 

 fraction being still further toned down by a dark glass. 

 At the moment of totality the dark glass was to be re- 

 moved, and a silver reflector pushed in, so as to get the 

 maximum of light from the corona and prominences. The 

 time of totality was distributed as follows: 



1. Observe approach of shadow through the air: totality 



2. Telescope 30 seconds 



3. Finder ..,.,.. 30 seconds 



4. Double image prism , . 15 seconds 



5. Naked eye 10 seconds 



6. Finder or binocular 20 seconds 



7. Telescope 20 seconds 



8. Observe retreat of shadow 



In our rehearsals Elliot stood beside me, watch in 

 hand, and furnished with a lantern. He called out at 

 the end of each interval, while I moved from telescope 

 CO finder, from finder to polariscope, from polariscope to 



