42 J. Wixierhoiifie—Jn Account of the Tidal [No. 1, 



During the monsoon of 1874 this duty was performed entirely by Capt. 

 Baird, who had generously given his assistant leave of absence on urgent 

 private affairs at that time. It had, however, proved to be so arduous and 

 to entail so much exertion and exposure, that Colonel Walker felt he would 

 not be justified in requesting Capt. Baird to carry on the inspections 

 during the monsoon of 1875. He was therefore directed to continue the 

 registrations up to within a few days of the commencement of the monsoon, 

 and then to dismantle all the stations, and remove the instruments. 



Accordingly at the close of the field-season of 1874-75, the instruments 

 were taken down and the observatories dismantled. At each station the 

 vertical iron cylinder, in which the float of the guage had acted, was left in 

 statu quo, together with a length of the iron piping, extending about 50 

 feet seawards from the cylinder. The cylinder was filled with clean dr^ 

 sand, and closed above with a thick planking, after which a massive pile of 

 stones was raised over the ground around it, to serve the double object of a 

 protection and an indication of the position for future reference. 



The three bench-marks in the immediate vicinity of the cylinder, with 

 each end of which the datum of the guage had been connected, were similarly 

 covered over. Finally the several cairns were placed under the protection 

 of the local officials ; and it is to be hoped that the cylinders and bench- 

 marks will be readily discovered whenever the second series of operations 

 are commenced, and that they will be found to have remained undisturbed 

 meanwhile. 



Thus the periods during which the tidal heights have been continuously 

 registered at the three stations are, IG^ months at Okha, 14 months at 

 Hanstal, 2 months at Nawanar in 1874 and 2 months more in 1875. As 

 already noticed, simultaneous observations of the direction and velocity of 

 the wind and of the barometric pressure were made by the anemograph and 

 barograph which were set up at each station. 



The long break in the registrations at Nawanar is to be regretted. But 

 as the station lies nearly midway up the Gulf, it is probable that the values 

 of the difference between the mean level for the periods of actual obser- 

 vation and the mean level for the entire year, which are given by the regis- 

 trations at Okha and Hanstal, may be applied proportionately to the results 

 at Nawanar, to obtain the mean level for the year there, and Capt. Baird 

 found that this plan gave very accordant and promising results. 



When all the observations were completed, the ordinates of the several 

 curves were measured, (taking full account of clock-error whenever there 

 was any) and then tabulated for each hour of the day. The numerical re- 

 sults thus obtained serve as the data on which the analysis of the obser- 

 vations was subsequently based. 



Thus ended the first series of operations, to determine whether the 

 relations of land and sea are constant or changing. Col. Walker writes : 



