18 bULLETIN OF THE UNITED STATES FISH COMMISSION, 



broken arch extended through the con stel hit ions of Cygnus, Cassiopeia, Gemini, and 

 Aurii/a, sometimes fainter, sometimes more tiery, especially in CygnMs. Very seldom 

 the red color filled the space between the rosy spot below Ursa mujor and the upper 

 arch, and then only for a few seconds. At 11 p. m. the sky became so overcast as to 

 cut off further observation. 



Corresponding observations made at St. Paul Island, Tribylof group, from 1872 to 

 1883, and published by the United States Weather Bureau (Fur Seal Arb., ii, App. 

 pp. 591-593), atVord means of exact comparison between the Eussian and the American 

 seal islaiuls, except as regards mean temperature, the latter being obtained on St. Paid 

 from observations made at 7 a. m., 2 p. m., and 9 p. m. 



But even a comparison of the mmn icniperafure aflbrds several very interesting 

 results. Thus, while the annual means apparently differ but slightly, there is also the 

 same relative proportion between the various months frotn December to September. 

 But while the figures representing the mean temperatures for these months are higher 

 on Bering Island than on St. Paul, those of October and November are higlier on the 

 latter. The chief exception from the relative proportion between the months is shown 

 by the mean temperatures of August, which is about 4 degrees higher than Julj' and 

 September in Bering Island, but only about 2 degrees in St. Paul. 



Turning now to the maximum temperature, it will be seen to be 63° F. in Bering 

 Island as against 62° on St. Paul. But on the other hand, while the minimum 

 temperature in Bering Island was hardly ever below zero during the four years of 

 observation, it often drops below that iioint in St. Paul. Thus, the difference between 

 the summer and winter extremes is less on Bering Island than on St. Paul. 



(Jomiiig now to the question of cloudiness, it will be seen that while the annual 

 percentage is almost identical, the monthly distribution is radically different. Thus, 

 while in St. Paul Island there are five times as many clear days during November to 

 April as during May to October, on Bering Island the projiortion is reversed, there 

 being four times as many clear days during the latter period as during the former. 

 Of fair days, St. I*aul enjoys nearly twice as many during tlie above six winter months 

 as during the six summer months, while Bering Island has a good many more fair 

 days in summer than in winter. Consequently, the entirely overcast days i)repon(ler- 

 ate on St. Paul in summer, while on Bering Island their number is greater in winter. 

 The latter island, moreover, has about 10 per cent more overcast days during the whole 

 year, but on the contrary also about 10 per cent less overcast during the summer 

 months, or during the time the seals remain on the islands. 



Unfortunately the ijercentage of relative humidity is not given for St. Paul Island. 

 A glance at the table for Bering Island will show how excessively humid the climate 

 of the latter is, the annual means reaching 90 per cent, the monthly means occasion- 

 ally exceeding 95 per cent, and never lower than 82 per cent. The months showing 

 the greatest percentage of relative humidity are July and August. 



The Weather Bureau tables alluded to do not contain any data relating to jyre- 

 cipitation on St. Paul Island, and all the published information I have been able to 

 find relates only to the months May to November.' Compared with the corre- 

 sponding tables for Bering Island, they show thiit the precipitation on the latter island 

 is considerably smaller during that ])eriod than on St. Paul Island. 



■ Fur Seal Arb., viii, jip. 518-519. 



