1878.] Olservations in the Gulf of CiUch. 29 



masonry platforms constructed on shore at the high-water line. It is 

 obviously desirable that the communication between the surface of the 

 ocean and the gauge should be as direct as possible, in order that the tidal 

 curve may be accurately delineated. Thus, it is usual to erect tide-gauges 

 in ports or harbours where the piers, quays and landing-stages constructed 

 for the requirements of the shipping present facilities for their being set 

 up in the vicinity of deep water. In the Gulf of Cutch, however, the 

 stations were all at a distance from the nearest inhabited localities and 

 presented no facilities whatever ; for not only building materials and food 

 for the workmen, but even fresh water, had to be brought to them from 

 considerable distances. It was thus imperative that the plan of operations 

 should be of the simplest nature possible, so as to be carried out with the 

 least cost and the greatest expedition. Had any jetties or piers been 

 available for the operations the stations would have been erected on them, 

 but under existing circumstances it was only possible to conhect the tide- 

 gauges with deep water by erecting stagings for them in the sea ; and these 

 would have had to be very strongly built to withstand the full force of the 

 sea, without undergoing any displacement whatever, and that, not for a 

 short time only, but for several years, so as to include both the first series 

 of tidal registrations, taken to determine the present relations of the land 

 and sea, and the final series which will have to be taken to determine the 

 future relations some years hence. The stagings would, moreover, have 

 had to be connected with the land by piers, in order to permit of ready 

 access to the instruments at all times. The cost of such stagings and their 

 connecting piers would have far exceeded the funds available, and therefore 

 Col. Walker decided, though with some reluctance, on having the tide- 

 gauges set up on shore, over wells sunk near the high-water line and con- 

 nected with the sea by piping. 



Final Arrangements. — The following is a brief sketch of the arrange- 

 ments adopted : 



Masonry wells of a diameter of about 8 feet were sunk at the stations 

 to a depth of several feet below the lowest tides ; in these wells iron cylin- 

 ders with an internal diameter of 22 inches, slightly exceeding the diameter 

 of the float of the tide-gauge, were set up vertically and connected with the 

 sea by an iron piping carried along the shore down to the low-water line, 

 where a flexible piping was attached and carried out into deep water. The 

 flexible piping terminated in a rose suspended by means of buoys a few feet 

 above the bed of the sea, in order to prevent the entrance of silt as muqh as 

 possible, and was attached to the iron piping in such a manner that it might 

 be readily removed and cleaned whenever necessary. The tide-gauges were 

 set up over the cylinders, and their iron bed-j^lates indicated the planes to 

 which the tidal measurements were referred ; they were connected by 



