498 PHILOSOPHICAL TRANSACTIONS. [aNNO I7O9. 



highest and lowest stations of the tnercury, as it was either at Paris or Up- 

 minster. For at Zurich the difference was only one inch Paris measure ; but at 

 Paris it was one inch 2-i- lines ; and at Upminster it was l^, which is greater 

 than either of the other two. On the whole, however, there is a considerable 

 agreement between the two barometers, the one being very often high or low, 

 when the other is so; and this one often rising or falling when the other does: 

 also the one rising much or little, or falling much or little, when the other 

 does: but though the matter is often thus, yet it is not so certainly so, as it is 

 nearer home. In our Philos. Trans. N° 286, I have given a table of some 

 heights of the mercury observed at Upminster, and at 200 miles distance in 

 Lancashire at the same time. And in the Hist, de I'Acad. Roy. des Scien. 

 Anno 1699, M. Meraldi, by comparing his observations at the Paris observa- 

 tory with mine at Upminster, remarks, *' That there is a great agreement be- 

 tween the variation of the heights of the barometers in both places ; that he 

 finds almost always that when the one rises or falls, the other does so too, 

 though not always alike: that the days in each month when the mercury has 

 been highest or lowest, it has been the same at Paris as at Upminster, but com- 

 monly somewhat more than three or four lines lower at Paris than at Up- 

 minster." But the agreement between the variations of Dr. Scheuchzer's 

 barometers and mine, although I say often great, yet is not so constantly, nor 

 so certainly great, as nearer home, viz. at London, Lancashire, Paris, and 

 other places, with which I have made the comparison. 



With regard to the rain, the first thing that presents itself to our view, is, 

 that the rains for the most part are more frequent at Upminster, than either at 

 Zurich or Pisa, in Italy ; that is, we have more rainy days than they. But yet 

 the rains in both these places are much greater in quantity, in the whole year, 

 and in some months, especially the autumnal and winter months, than our 

 rains are at Upminster. As to Zurich, I observe, that although the rains there 

 are less frequent than in Essex, yet they seem more so than at Pisa : but the 

 quantity at Zurich is greater than at Upminster, and less than at Pisa. It is 

 Dr. Scheuchzer's opinion, " That more rain falls in Switzerland than in France, 

 at Zurich than at Paris." To confirm which, he gives a table of the last 8 

 years rain at Paris, from which, and from mine at Upminster, it appears that 

 in the 8 years, there fell at Paris 1524- inches English measure, but at Up- 

 minster 154-1^ inches in the same years; which give for the medium per year, 

 19 inches and IQf inches, respectively. Where it may be remarked, that 

 there is a greater difference between these last 8 years rain at Paris and Up- 

 minster, from what I found in the 8 years, in which I formerly compared the 

 rain of TgWHC}^y> JPajris, IJisl^, jMid. Upminster together, in the Philos. Trans. 



