without slackening speed. The following table shows the dimensions of the principal ship canals in the world:1

N.B.-The dimensions given are taken at mean low water.

1

Mr. Menocal says: "The conditions at Suez cannot be compared to those in Nicaragua. There nearly the whole canal is in excavation, and the enlargement is done to enable vessels to meet at any point instead of at certain turn-out places only, which causes much loss of time, and frequent grounding in getting into and out of the turn-outs. The large section is caused by the flat slopes and wide beams made necessary in the loose sand through which the canal passes, and the difficulty of getting suitable material for protecting the slopes.

In 1885 an "International Commission" proposed a scheme for the enlargement of the Suez Canal. It contemplated the deepening and widening in successive stages to be extended over many years, the

The following tables give the length of the different sections of canal in excavation in the lake, the river San Juan, and through the basins:

capacity to keep pace with the growing demands of traffic. In 1886 the work of deepening was begun, and in 1889 the depth had been increased throughout to 8.50 metres (27'9 feet). The widening was then begun, and is still in progress. It is carried on only on one side of the prism, the increase in width being 15 metres (49'2 feet). In 1890, 3,389 vessels of 9,749,129 tons passed through the canal, through what was then, and is practically yet, the original prism. It is doubtful whether the widening will ever be done on the other side of the canal, except, perhaps, in some of the sharper curves, and if pushed at the present rate, the whole cannot be finished for a score of years."

The dimensions of the greatest war-vessels are: length, 380 feet; breadth, 75 feet; draught, 28 feet.

HARBOURS AT TERMINI.

THE GREYTOWN HARBOUR.

The harbour at Greytown about the year 1833 was still one of the finest harbours along the Caribbean

coast, and some thirty-five years ago was yet a good and safe port, with an inner bay, having 20 to 30 feet of water inclosed from the sea by a narrow sand spit extending from the main shore on the east to within a few hundred feet of the mainland to the west. The westerly advance of the spit by the shifting sands, under the

influence of the north-east winds and waves (the trend of the coast is nearly south-east to north-west), had been gradually contracting the entrance for a long period. The channel became quite narrow, with only some 25 feet of water opposite the extremity of the spit, and nothing being done to check its progress, the spit continued to encroach, and about 1860, the harbour became a lagoon, separated by a sand-bank from the sea.

To open and maintain a practicable entrance, and generally to restore the harbour, the usual device of building a long jetty normal to the shore line has been adopted. This jetty will project seawards about 3,000 feet to the six-fathom curve, and dredging, under its lee, will be done to form an entrance into the lagoon, which will be deepened over an area of 200 acres to the uniform depth of 30 feet. The shifting sands, it is claimed, arrested by the breakwater, will gradually gather in the east angle formed by it and the coast, and will cause a gradual advance seawards of the new shore line, in the course of time shoaling at the end of the pier, with a tendency to move round and form a new bank across the entrance. This can be avoided, Mr. Menocal believes, by short extensions of the jetty from time to time, as may be required, until the new coast line becomes, in its general direction, perpendicular to the prevailing north-east winds, when no further change need be apprehended, and the permanent restoration of the harbour will have been accomplished. To appreciate the probable action of the jetty, the local conditions must be briefly noted. Firstly, this part of the Caribbean coast is in the heart of