DEFLECTION OF LIGHT—DYSON AND OTHERS. 159 
of the clouds was due to the eclipse itself, as it was noticed that 
the sky usually cleared at sunset. 
It had been intended to complete all the measurements of the 
photographs on the spot; but owing to a strike of the steamship 
company it was necessary to return by the first boat, if we were not 
to be marooned on the island for several months. By the inter- 
vention of the administrator, berths, commandeered by the Portu- 
guese Government, were secured for us on the crowded steamer. We 
left Principe on June 12, and after transshipping at Lisbon reached 
Liverpool on July 14. 
30. The following is a list of the photographs, including the 
comparison photographs kindly taken for us by Mr. F. A. Bellamy 
at Oxford, before the instrument was dismounted. All the eclipse 
photographs are given though only W and X furnished results. Of 
the other series only the exposures actually used jn the reductions 
are given. 
List of plates. 
Check Field (R. A. 14h. 12m. 47s., declination + 20° 30’). 
Local sidereal] Expo- | Approx.| Barom- | Ther- 
Reference. Place. Date. time. sure. Z.D. eter. |mometer.| Flate 
1919 emis s Ss $ in 3 
Chak POO Oxford Jan. 16 12 *55 “10 60 35 29. 64 37.0 i) 
Bynes MOUS by do... 17 13 10 40 60 34 29. 83 35.3 S 
Ce ee Wor ee 17 13 54 55 60 31 29. 83 35.3 iS} 
ES OO eC) ee do 17 14.9 25 60 31 29. 83 35.3 s 
(EGER a en Gone 255 23 Teeedox) BO 60 33 30. 45 29.0 Ss 
Greenwich Expo- | Approx. | Barom- Ther- 
Reference. Place. Date. | meantime. | sure. ap: eter. |mometer.| Fate. 
1919 Wem Us. .8 $ ° in 5 
Wie anise cacao Principe May 22 12 25 40 40 43 29.45 76. 5 S.R 
Thee acts Leek] SSE doseii.t 22 12 31 20 40 45 29. 45 76.5 S.R 
aE eke cpus Boss csxe 22 12 37 50 80 46 29, 45 76.5 S.R 
OP SABES ERS Beton Gems Gots. 25 12 22. 20 40 45 29, 45 76.5 S.S 
Cap is desea bodies | tll do: fs. <2. 25 12 26 20 40 46 29, 45 76. 5 s.s 
Eclipse Field (R. A. 4h. 19m. 30s., declination +21° 43’). 
Local sidereal) Expo- | Approx. | Barom- Ther- 
Reference. Place. Date. time. sure. 7 D. eter. |mometer.| Fate- 
1919. h. ™. 8 ° in. ‘A 
Die gue ccesien Oxford..-.| Jan. 16 3) 58% .41 5 30 29. 65 39.0 s 
Giese ge ek do.. 22 4 4 39 5 30 30. 30 31.0 s 
15 & (eyes aan a [eas do.2o 2%: 22 4 34 28 5 30 30. 30 31.0 Ss 
TRAE Shas REL dose 5A 22 4 48 46 10 31 30. 30 31.0 s 
Tigi eats ee ee a als dois his. Feb. 9 4 45 24 10 30 30. 48 24,5 Ss 
