698 PHILOSOPHICAL TRANSACTIONS. [aNNO 1780. 



1014; the weather was fair and cold, but not frosty. This spot is reckoned 

 very healthy; the inhabitants have a sound look, and generally live to a great 

 age. Nov. 28, the air at Rotterdam was at 103; the weather rainy and cold. 



Nov. 29, being at Delphi, I gathered some air in the middle of the day, the 

 weather being stormy and rainy. I examined it next day at the Hague, and 

 found it at 103; and that of the Hague 104. Nov. 30, the air at the Hague 

 was at 104; the weather cold, the wind northerly. 



Dec. 1, being still at the Hague, the weather underwent a sudden and remark- 

 able change. The wind was southerly and stormy; the air was become so warm, 

 that on going out of the house into the street, I felt the same sensation as on 

 going from a cold air into a room heated by a German stove. I suspected that 

 this sudden change would alter the constitution of the atmosphere in point of 

 salubrity. Having no time to make any experiment, I contented myself with 

 filling some phials with this air, and sending my servant to Schevelingen to ga- 

 ther some air close to the sea. Dec. 2, the wind and weather remained the same 

 as yesterday. In the evening, about 8 o'clock, when Fahrenheit's thermometer 

 stood at 54°, I put the common air to the nitrous test, and found it at 1 16; the 

 air gathered the day before at 1 17'. and that gathered close to the sea at 113. 

 As I had never found the common air near so bad, I had some apprehension that 

 my eudiometer was out of order, or that something was the matter with the 

 nitrous air. I made therefore fresh nitrous air, and repeated the experiment 

 many times, but the result was nearly the same. In the mean time, I had the 

 following accidental meeting. The father of the landlady of the house having 

 been informed by the servant, that I was about some extraordinary pursuit, of 

 which he could have no conception, came to see what I did. He had scarcely 

 been a minute with me but I perceived he laboured under a severe asthma. 

 He explained his case to me, knowing me to be a physician, and told me, that 

 he had passed these 2 days very uncomfortably, finding the air so uncommonly 

 heavy, that he could hardly draw his breath : which convinced me that the ele- 

 ment was in reality become of an inferior quality. 



Dec. 4, at Amsterdam the air was at 103; the weather being rainy, windy, 

 and cold. Dec. 5, the air was at 102: the weather nearly as yesterday. Dec. 

 10, I returned to Rotterdam, and found the air at 101 ; the weather rainy. 



In the beginning of last year they made an end of draining a large ineer, 

 about half the size of the Haerlemmer Meer, situated in the neighbourliood of 

 Rotterdam, which was turfed out in former ages. It was now laid into arable 

 land and turned out to be very fruitful. When this land was quite cleared of the 

 water, an uncommon epidemical disease broke out in all the places situated on 

 the borders of this lake; it began about August, and abated when the winter 

 season set in. This distemper broke out afresh last summer, and was now again 



