Xvi 
the adjoining pier-stone (the seventh from the angle of the pier) 
and found to be 18°15 feet below it. 
IntsHcort.—August 26. There are no tidal observations at this 
station. The cistern of the barometer was found to be 4:2 feet 
above the base of the Lighthouse Tower. 
Kitrusu.—September 1. There was no re-measurement at this 
station, the tide-gauge having been destroyed by the violence of the 
sea. 
CanircivEEN.—September 2. The zero of the tide-gauge was 
found to be 23°50 feet below the provisional mark, which is on the 
upper surface of the coping-stone of the pier of the bridge, at the 
north-east angle. 
CAsTLETOWNSEND.—September 6. The zero of the tide-gauge is 
31:94 feet below the Ordnance bench-mark, which is at the foot of 
the flag-staff. 
Courtown.—November 11. The Ordnance bench-mark at this 
station is a bolt driven vertically in one of the coping-stones on the 
north side of the channel to the harbour. The zero of the tide- 
gauge is 17°13 feet below it. The cistern of the barometer is 25-14 
feet above the bench-mark. 
Dunmore East.—November 12. The Ordnance bench-mark is 
a vertical bolt driven into one of the coping-stones of the pier, not 
far from the Lighthouse. The zero of the tide-gauge was found to 
be 17:59 feet below it. 
The levellings taken at Portrush and Dunmore differ considera- 
bly in their results from those of the preceding year. This is due to 
the circumstance that the tide-gauges were not erected at these sta- 
tions when they were visited in 1850; and consequently, all that 
could be then done was to level from the bench-mark to some point 
near the intended position of the gauge, leaving the rest to be done 
by the observer. The measures taken in 1850 at these two stations 
must, under these circumstances, be disregarded. At all the other 
stations the measures taken in the two years are nearly accordant, 
and their means will be employed in the comparison of the mean 
tide levels. 
