65 



for two years, from June, 1866, to June, 1868, and before 

 the opening of the canal to the waters and navigation. 

 The observations embraced those of the barometer, thermo- 

 meter, and hygrometer, and have been tabuhited out by 

 months, and the means and ranges made out of each set for 

 the three stations of Port Said, Ismailia, and Suez. 



At Port Said the mean barometer was 29'94in., and its 

 range for the period only 'SSin. ; the mean thermometer was 

 68°-9 F., but the range was as much as 26° F., from 82°-l in 

 July to 5Q°-o in February. The mean hygrometer was 71, 

 with a small range of only 3 in consequence of tiie vicinity 

 of the sea. 



At Ismailia the mean barometer was 29'92in., with a like 

 small range of only "S^in., from the absence of storms ; the 

 mean thermometer was the same, or 68°'9 F., but with a 

 higher range of 28°, from its inland situation and drier air, 

 from 82°'o in July to 54°'5 in February. The mean hygro- 

 meter was here lower at 68°, but with a higher range of 19, 

 from 58 in June to 77 in December, which is probably due 

 to the presence of the neighbouring desert. 



At Suez the mean barometer was only 29'95in., with a 

 like small range of only -Slin. ; the mean thermometer was 

 at 69"o, somewhat higher than that at the other stations, 

 from being further south and surrounded with hills, and 

 with a high range of 27, from 83°1 in July to oa^'S in 

 February. The mean hygrometer was a,t 64, or much less 

 than at the other stations, with a still higher range of 23, 

 from 49 in May to 72 in December, due to the neighbouring 

 desert and its clear sky and dry air. 



On summarising the tables for the estimation of the 

 general climate of the canal and district, the mean barometer 

 was found highest in the winter months of November 

 (3006in.), December (30-04in.), January (3007in.), and Feb- 

 ruary (SOlOin.), and lowest in the summer months of July 

 (29"76in.) and August (29-78in.), owing to the variation in the 

 positions of the zones of high and low pressure over Egypt in 

 the winter and summer isobaric lines. The mean thermometer 

 at all the stations was highest in the summer months of 



