On the Horary Oscillations of the Barometer at Rome. 117 



neglected, as a very small difference of level would occasion it. 

 The Collegio Romano stood nearly on the same street, and on 

 very flat ground, and the level of both barometers was proba- 

 bly almost exactly the same, viz. about 1 20 feet above the sea. 

 Hence I assume the heights given to be correct, and the 

 neutral point is considered at 30.000 inches, as this agreement 

 took place only -^^q lower. The capillary attraction of the in- 

 strument comes to be by Mr DanieU's estimate in boiled tubes 

 0.044. The instrument during the whole observations hung 

 in the same spot, except a few days in January, (including the 

 12th and 15th,) when, though in another house, I consider the 

 difference of level to have been next to nothing. As to the 

 precautions taken to ensure accuracy, I shall simply state, that 

 every one of the observations has been made with great care 

 hy myself personally, excepting only one or two morning ones 

 on the 12th and 15th January ; that the whole corrections and 

 calculations have been performed by myself from the best da- 

 ta; and that in the whole series not a single dubious obser- 

 vation has been made use of. I now give the first table, 

 including the original observations, as transferred to my re- 

 gister. 



