Apkil 



o. 



1885.] 



SCIENCE 



271 



suffers less from the direct rays of the sun, and 

 not at all from the reflected and radiated heat. 

 As the entire route from Suakin to Berber is 

 subject to heats fully equal to those of the 

 vicinity of Suakin, it may be safely asserted 

 that it is impracticable for European foot- 

 soldiers to make the march between those 

 two points during the spring and summer 

 months, except by using the night and early 

 morning exclusively for marching. 



The climate of the province of Berber is 

 very similar to that of Dongola ; but, owing to 

 the effects of the waters of the river Atbara, 

 in some parts of this province fevers are more 

 prevalent during the summer months, and of a 

 worse type than in Dongola. 



In the province of Taka and the district of 

 Gallabat, the climate from June to October is 

 deadly for Europeans. During that season the 

 rains are there copious, and, mingling with 

 the floods of water coming down from the 

 mountains of Abyssinia, cause the rich soil 

 to become like a saturated sponge, while the 

 rank vegetation and the exhalations from the 

 soil render the air poisonous. From many 

 districts the natives abandon the country in 

 May, taking with them their families, their 

 flocks and their herds, — to save themselves and 

 their families from fever ; and their flocks and 

 herds from the ravages of the stinging insects 

 which, during the season of rains, infest the 

 country. These people go north to the deserts, 

 and remain until the latter part of October, 

 when they return, to find their own country 

 delightful in climate, and glorious in vegetation. 

 These conditions remain through the winter, 

 and the air is healthful until April. 



The climate of Khartum is hot, damp, and 

 exceedingly unhealthy from April until Octo- 

 ber. The winter climate is not disagreeable ; 

 but even in winter the place can hardly be 

 considered healthy, owing to the peculiar loca- 

 tion of the town between the Blue and White 

 Niles, and to lack of sanitary rule in the con- 

 struction of the streets and houses. During the 

 past twenty 3'ears, more care has been taken 

 in the construction of dwellings ; and the con- 

 ditions are now more favorable than they for- 

 merly were. 



The province of Kordofan is visited by less 

 rain than that of Khartum or of Taka. During 

 the winter, from the last of October until the 

 1st of March, the climate is very agreeable 

 and quite healthy. The prevailing winds are 

 from the north. The temperature is not high, 

 ranging in the middle of the day from 80° to 

 88° F. The air is bracing and invigorating, 

 while the nights are cool and pleasant. 



March, April, and May are there the hottest 

 and most disagreeable season, though not un- 

 healthy. In June the season of rains com- 

 mences, and it lasts until the latter part of 

 September or early October. The winds are 

 then from the south and south-west. The rains 

 come in showers, sometimes daily, but oftener 

 once in three or four days. The air is debilitat- 

 ing ; and fevers, intermittent in form, strike all. 

 excepting the natives. 



No matter what care may be taken to guard 

 troops from the effects of climate, the death- 

 rate among soldiers is always great during this 

 wet season. In an expedition which I sent 

 into that province, well organized, well and 

 very carefully commanded, well supplied, with 

 good medical attendance and good hospital 

 supplies, six per cent of the soldiers died 

 during four months of the season of rains, 

 while during the remainder of the year there 

 were very few deaths. 



The climate of Darfur closely resembles 

 that of Kordofan. The rains come at the same 

 time of } T ear, and the sanitary effects of the 

 different seasons are nearly the same ; yet the 

 fevers, according to the reports of the medical 

 officers, seem to be more often severe in type 

 in Darfur than in Kordofan. C. P. Stoxe. 



THE CAROLINE ISLAND ECLIPSE EX- 

 PEDITION. 



The protracted duration of totality of the 

 eclipse of May, 1883, early attracted the atten- 

 tion of astronomers ; but an examination of its 

 shadow-track on the earth showed the unfortu- 

 nate fact that it would begin in the Pacific just 

 east of Australia, and completely traverse the 

 ocean, finally leaving the earth before the South 

 American continent was reached. Only one 

 eclipse had ever been observed with a greater 

 duration of totality ; and the possibility that 

 an observing-station might be available in the 

 small islands of the South Pacific determined 

 Mr. Charles H. Rockwell of Tarrytown, X.Y., 

 to endeavor to organize an observing expedi- 

 tion from the United States. Through his 

 representations, the National acaclem}' of sci- 

 ences was brought to consider the matter, 

 and it was expected that Professor Young of 

 Princeton would have the entire charge of the 

 expedition. Unforeseen circumstances pre- 

 vented this, and the party was finally organ- 

 ized with Professor Holclen as chief, and sci- 



Report of the eclipse expedition to Caroline Island, Jfay, 

 1883. In vol. ii. of the Memoirs of the national academy of sci- 

 ences. Washington, 1884. 146 p., 22 pi. 4°. 



