SCIENTIFIC JOTTINGS IN EGYPT. 823 







Pneumonia. Natives of the tropics, and more especi ally- 

 negroes, whether at home or abroad, are peculiarly subject to 

 this acute fever. The death-rate and average of severe cases are 

 among them exceptionally high. 



Phthisis is also remarkably rapid and frequent with these 

 races when sojourning for many months in cold climates, but less 

 so with the southern Asiatic. The Practitioner. 







SCIENTIFIC JOTTINGS IN EGYPT.* 



By De. H. CARRINGTON BOLTON. 



THE following pages record impressions and observations made 

 in the spring of 1889, during a brief sojourn in the Nile Val- 

 ley, and a more deliberate study of the Sinaitic Peninsula. In 

 discussing one's experience on a journey the weather claims early 

 notice. In February, at the hotel in Cairo, the thermometer ranged 

 from 60 at 8 a. m. to 78 at 3 p.m.; but on the Nile steamer much 

 greater extremes were noted, 54 at midnight (February 19th) 

 to 87 at 2.30 p. M. (February 9th). In the shade the heat was 

 rarely oppressive. 



The temperature in the desert in March was favorable to the 

 traveler's comfort, with rare exceptions ; the thermometer ranged 

 from about G0 to 80 in twenty-four hours at the sea-level, and 

 from 48 to 75 at the elevation of about five thousand feet. 



The highest evening temperature was on March 17th, after the 

 khamsin had blown all day at 7 p. m., 84. The lowest temper- 

 ature observed was on March 20th, in camp about three thousand 

 feet above the sea at 6.30 a. m., 33. (In February, 1874, Rohlf 

 noted in the Libyan Desert a minimum temperature of 23.) In 

 considering the physiological effects of these temperatures one 

 must remember the extreme dryness of the atmosphere in the 

 desert. 



My first experience in Egypt was calculated to give the im- 

 pression that it is a rainy country, for I saw two showers in 

 three days. In passing through the Suez Canal (January 31st), 

 a heavy shower, lasting half an hour, drove the passengers to 

 shelter, and a brilliant rainbow delighted beholders. Two days 

 later, rain again fell at night in Cairo, making the dirty streets 

 more nasty still. Of course this experience was exceptional, as 

 rain is a rarity in Cairo. Authorities give the rainfall at Alex- 

 andria as about eight inches per annum, and at Cairo about 



* Abstract of a paper read to the New York Academy of Sciences, February 24, 1S90, 

 and condensed by the author from the Transactions, vol. ix, p. 110. 



