inches, whilst the averages for maximum temperatures, minimum temperatures 
and barometrical records were 82°0° F., 61°29 F., and 24°81 inches respectively. 
During the three and a half months spent at Lan-chou the barometer 
varied from 24°60 inches to 25°30, an extreme variation of 07 inch. The 
barometer at T’ai-yiian during the three months ending July 31st shewed an 
outside variation of only 0°42 inches. 
On July 15th the expedition left Lan-chou Fu on its way back to T’ai- 
yiian Fu, by the same road which it had travelled in the spring. The journey 
occupied nearly two months, during the whole of which time careful 
observations were kept. No long stoppages were made. 
On the 17th the party was held up for two days at Ch’éng-kou-yi by very 
heavy rains, which rendered the roads through the soft loess country 
impassable. The rainfall recorded on this occasion was 1°32 inches in ten 
hours. Unfortunately the rain gauge overflowed during the night so that it 
was impossible to estimate the exact amount that fell. The head native of the 
expedition said that it was the heaviest rain he could remember since the time 
(about 1888) when the Fén Ho overflowed. It then flooded the T’ai-yiian 
plain, and, entering that city, demolished the Tartar quarter in the south- 
western corner. 
At Ch’ang-t’ai-p’u the expedition was again held up by rains from the 
evening of the 25th to the 28th. During this time a total of 1°45 inches 
fell. Altogether the total rainfall for the month was 4°33 inches. The 
weather was usually bright and calm, though frequently very hot. 
August found the expedition once more at Ku-yiian Chou, and for some 
days the weather was fine and calm. Rain fell on the 4th, after which the 
party experienced intermittent rain, overcast skies, heavy dews and mists till 
the 25th. The total rainfall for the month was 1°63 inches. From the 
25th to the 31st the weather was again clear and calm. During the whole 
month there was scarcely any wind. 
On the 5th the thermometer registered a maximum temperature of 102.2° 
F. at Ching-yiian Hsien, and gg‘0° F. was recorded at Ch’ing-yang Fu. 
four days later. 
From this date the temperature seemed to fall steadily though some very 
hot days were experienced in the loess ravines of the country between Yen-an 
Fu and Sui-té Chou, which place was reached on the 2gth. 
The first three days of September were wet, the rainfall being °52 
inches. From then onwards the weather was clear, with but little wind. The 
151 
