George. — Description of Patent Slip at Wellington. 19 



was rock, neai-ly the whole width of the ways ; on one side, however, the rock 

 dipped below the surface some few feet. 



After the centre line of the slip was set out, sighting poles were erected 

 at various distances up the hill at the head of the slip, and also on the opposite 

 side of the bay, at the distance of about three-quarters of a mile ; the centre 

 line could, therefore, be readily checked at any time, and the poles serve to 

 direct a vessel when going on the slip. 



The material from the excavation served to reclaim portions of the beach 

 about the site of the slip, forming available ground where strips of sand and 

 swamp previously existed. On the completion of the excavation, the work of 

 laying the ways was proceeded with. The process above high-water mark 

 was exceedingly simple. A traveller was erected over the ways at high- water 

 mark, which was moved up the cutting as the laying of the rails pi'ogressed ; 

 the sleepers were bolted to the ways before being placed, and, the ground 

 being excavated, the whole were placed in position together by means of the 

 traveller. Four men only were required to carry on this work, viz., two 

 labourers to excavate for the sleepers, and two mechanics to fit up and fasten 

 the ways and sleepers in position. Each length, as placed, was levelled by 

 means of a spirit level and straight-edge bevelled to suit the gradient of 

 1 in 23, the centre line being checked periodically with the distant sights with a 

 theodolite. The ti'aveller used for laying these ways afterwards served to erect 

 the carriage, which was erected in its place on the ways. Simultaneously with 

 the work above high water, the work of laying the ways below high-water 

 mark was proceeded with — a much more tedious and difficult operation. At 

 high-water mark a frame was erected across the ways for conveniently lifting 

 the different parts on to the small carriage used for lowering the various 

 lengths out below water, until a depth of about 6ft. of water was reached; 

 the ways were placed in position by means of a traveller working on trestles 

 placed on each side of the ways, A work that occupied considerable time, 

 and proved a much greater expense than was anticipated, was the excavation 

 of the rock below water. The excavation was effected during low water as 

 far out as possible, and the diving bell was then got to work to excavate and 

 remove the remainder. The bell was worked between two punts ; the engine 

 and air pumps for supplying the requisite air and driving the piles, and also 

 two pile engines, were fixed on the punts. The men in the diving bell worked 

 in shifts of four, five, or six hours, as cii-cumstances required. This work 

 could not be carried on during the night, as no means could be adopted to 

 correct the levels of the bottom in the dark. If too much had been removed, 

 greater expense in fixing would have been incurred, and more concrete 

 required, without calculating the loss of time ; while, on the other hand, if 

 too little had been taken off. great difficulty would have been caused in 



