1843.] in Barometric Observations. 295 



days with one of Major Sykes' barometers, which I had filled and 

 boiled, in which also the mercury used to adhere to the top of the 

 tube. These two barometers used always to stand at the same 

 height within a thousandth of an inch about the middle of the tide, 

 but at the times of maximum and minimum, one of them used to range 

 about two-thousands above and below the other. The difference to 

 maximum and minimum being never less than '001, nor more than 

 '003. We considered them to be the most perfectly comparable of 

 any two barometers we had ever seen. Major Sykes' barometer 

 remained on the spot where the comparisons had been made, while 

 mine was carried to Bombay, and as the mercury still continued 

 to adhere to the top of the tube, it plainly had not been deteri- 

 orated by the journey. Our observations were made simultane- 

 ously at 10 a. m and 4 p. m. for several days successively, but 

 on calculating them, I found that the 10 o'clock observations 

 always gave the height of Puna about 100 feet more than 

 was given by the 4 o'clock observations. I ascertained beyond doubt, 

 that there had been no mistake of a tenth of an inch in registering 

 the observed heights. The like discrepancy continued at several 

 other stations along the Sea Coast. This discordance of result being 

 unvaried, naturally set me to consider what might be its probable 

 cause: and the only cause I have ever been able to discover at all 

 likely to account for the fact, is in the effect of the Sea breeze, which 

 at that season of the year begins to blow about 8 or 9 a. m. along the 

 coast, while towards Puna it is not felt till about 2 p. m. After 

 blowing over the low lands in the Konkan, it is intercepted about 

 midway by the Seihadri Ghats, which presenting an almost perpendi- 

 cular scarp of from 2000 to 3000 feet, cause the air to accumulate 

 over the low land, thereby increasing its barometric pressure to an 

 amount equivalent apparently to about a tenth of an inch of mercury, 

 corresponding to a column of about 100 feet of air, somewhat similar 

 to the head of water produced by an obstacle placed in its current. 



I am aware that some persons may be disposed to treat this state- 

 ment as of little authority, for want of the actual observations on 

 which it is founded. The fact, however, is tangible, and may be 

 submitted to proof or disproof by any one who chuses to make the 

 necessary observations. 



