92 Mr. Daniell on the Barometer. 



hygrometer, is not stated. If from the former, the situation of 

 the thermometer by which the calculation is made should have 

 been most particularly determined. 



The eighth column contains the register of the rain ; and from 

 the greater frequency with which the amount has been lately 

 entered, we mayconclude that the soot from the old chimney-cowl, 

 under which the gauge is situated, is more frequently removed 

 from the pipe than it used to be. 



The ninth and tenth columns, recording the direction and force 

 of the wind, bear every mark of their former accuracy ; and the 

 only remarkable fact is the very rare occurrence of any variation 

 of the strength from the standard 1. 



The eleventh and last column rings most edifying changes 

 upon " rain," f« cloudy," " fine." 



The results of all this labour are summed up at the end of the 

 journal in one short table, containing the means and extremes of 

 the months, and the mean results of the year. From what data, 

 or from what part of the register, the means of temperature are 

 collected, it is very difficult to conjecture. From the note at the 

 foot of the last page we learn that the barometer is now 100 

 feet, instead of 81, above the level of low water spring-tides at 

 Somerset-House; and that the rain-gauge is still 114 feet above 

 the same level ; but by some chance or other, six inches nearer 

 the ground than before. 



The importance which attaches to such minutiae as these, when 

 undertaken by such a body as the Royal Society, cannot be better 

 illustrated than by a circumstance which has lately been disco- 

 vered, in determining the length of the second's pendulum ; a 

 measure upon which depend all the late parliamentary proceed- 

 ings for regulating the weights and measures of the united 

 kingdom. 



The council, by whose orders the height of the barometer above 

 the level of the tide was determined, little foresaw at the time that 

 this simple operation could have any reference to proceedings of 

 such importance : and yet hear what Captain Sabine says. 



" The height of the pendulums in Mr. Browne's house, in Lon- 

 don, being here described as 92.5 feet above the level of the sea, 



