38 J. Watorliouso — Ait Account of the Tidal [No. 1, 



its narrowest jwint opposite to Wawania. Moreover the common unmetal- 

 led roads in a black-soil country, as is the western portion of Kattywar, be- 

 come all but impassible during the rains ; and thus Capt. Baird was often 

 unable to get over the ground more expeditiously than at the rate of about 

 a mile an hour. Between the 7th July and the 8th September he was 

 actually 38 days in the field, and marched nearly 800 miles under most 

 adverse circumstances. 



General Working oftJie Tide-gauges. — The general working of the 

 tide-gauges at the three stations has now to be noticed. 



At Okha the registrations went on most satisfactorily throughout 1874! 

 and the following field season ; there were very few breaks of continuity of 

 the records, and they were very short and of no importance. At Hanstal 

 where the water was very muddy, and not pure and clear as at Okha, the 

 breaks were more numerous and longer ; they were caused sometimes by the 

 driving-clock getting out of order, but more frequently by the deposit of fine 

 mud in the well and piping of the gauge, notwithstanding the precaution 

 which had been taken to keep the rose at the extremity of the piping high 

 above the mud-banks ; this necessitated the occasional susj)ension of opera" 

 tions while the mud was being removed, and care was always taken to make 

 the break between the times of high and low water, whenever possible ; thus, 

 as the record of the highest and lowest points of curves has been secured in 

 almost all instances, the breaks may usually be interpolated between them 

 by hand, in conformity with the collateral curves, without any risk of 

 significant error. The foreshore at Okha being sand and rock without 

 mud, there was no tendency there for the pipe to become choked. Both at 

 Okha and at Hanstal air was found to enter the iron piping, whenever the 

 latter was laid bare by the action of the surf, which frequently happened ; 

 but it was readily expelled at high-water, by opening the stop-cock which 

 has already been described as attached to the piping for that purpose. 



At Nawanar, matters went on less prosperously. When inspecting 

 this station in July 1874, Capt. Baird found everything apparently in good 

 order ; the curves on the diagram seemed at first to be all that could be 

 desired, but it was soon evident that they were erroneous, for the level of 

 the water in the well differed very sensibly from the sea level. On examin- 

 ing the piping, the extreme end was found to be buried in sand above the 

 low-water line, at a spot where a few weeks before, there had been a depth 

 of 20 feet of water at low tide, but which was then left bare for some 

 time daily. On further examination it was ascertained that the configura- 

 tion of the foreshore had entirely changed, and an extensive sandspit had 

 formed on the line of the piping ; this had been caused by the drift from 

 a belt of sand-hills to the south, under the influence of the strong winds 

 which blew from the south-west during the monsoon, the registered veloci- 



