Geoege. — Description of Patent Slip at Wellington. 15 



prevent the carriage running back. The outer ways are of the section of an 

 ordinary I girder, with a rail cast on the top. The distance apart from centre 

 to centre of outer ways is 30 ft., the ways being kept to their proper gauge by 

 means of cast iron stays placed at intervals of 18 ft., and bolted to the ways. 

 The ways are cast in lengths of 9 ft., the faces of meeting, or ends, being faced 

 or planed so that a correct joint and continuous bearing surface is produced, 

 each length being bolted to the other by bolts passing through the end flanges. 

 Above high-water mark the ways are bolted to sleepers of hinau or totara 

 12 in. X 10 in., the sleepers being 3 ft. apart from centre to centre, the centre 

 sleepers being 6 ft. in length, and the outer ones 3 ft. The greater portion of 

 the surface consists of rock, which was excavated to the required depth to 

 admit the sleepers and ways, which, after being accurately levelled and graded, 

 were grouted in with Portland cement, and the ground levelled up to the 

 bottom of the rail with rubble. In one or two places the ground was too soft 

 to carry the ways with safety in this mannei', and in these cases piles were 

 driven to depths varying from 5 ft. to 15 ft., to which the sleepers were 

 secured. Below high-water mark the ways or rails are bolted to cross sleepers 

 of totara, 33 ft. in length and 12 in. x 10 in., at intervals of 3 ft. centres; 

 four piles being driven under each sleeper, until a depth of 14 ft. of water at 

 high tide was reached. This depth being sufficient to allow 8 ft. of water 

 over the carriage, it was not considered necessary to extend the piles beyond 

 this depth, as a large vessel would weigh very little on the carriage when 

 drawing this amount of water. Beyond this depth, four longitudinal timbei"s 

 were laid under the sleepers, two being under the centre rail, and one under 

 each of the outer rails. Where the contour of the bottom of the bay differed 

 from the inclination or gradient of the ways, cast ii*on stanchions or columns 

 are introduced between the sleepers and the ways. The whole of the timber 

 is covered with concrete to protect it from the ravages of the worm. 



It was contemplated when the slip was designed, that the site on which it 

 was to be fixed would be su.fficiently solid to carry the ways or columns 

 without the intervention of sleepers. The cost of the material would have 

 been considerably reduced had the exact nature of the bottom been known 

 when the design was prepared. The actual weight per foot run of ways and 

 stays, or distance pieces, is about 7 cwt., and to this has to be added the weight 

 of the columns or stanchions, as well as the bolts and other fastenings. 



The total length of the ways laid down is 1,050 ft. The gradient, or 

 inclination, is 1 in 23. At the end of the ways, a stop is fixed in the centre 

 line to prevent the carriage from over-running the rails when a vessel is 

 launched. The carriage or cradle is 250 ft. in length on the centre beams, and 

 is made in two pieces; the principal length, which is 180ft. long, being 

 sufficient to accommodate the class of vessels now frequenting the port of 



