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and, of course, are laid with the grain vertical. A 5 in. or 6 in. concrete base is usually used, and the blocks are either laid on a cement-sand cushion or the base is painted with asphalt and the blocks laid diiectly on it. A bituminous filler is then thoroughly mopped into the joints, and is followed by a coating of coarse sand. 'ri In London creosoted soft-wood blocks are still being used extensively. A very heavy concrete base is first put down, and finished off accurately to template with 2 in, to 3 in. of fine aggregate concrete and grout, making a total thickness of about 12 in. Tho blocks are then laid without any cushion, and a coating of tar, cement, and sand or small chips applied later. The blocks are laid with their length at right angles to the traffic, with the exception of two rows adjoining each channel. An expansion-joint, 1 in. in width, is left next the channel, and is filled with pitch. The blocks are very accurately sawn. Little care is used in curing the concrete base. Taking into consideration the great deal of horse traffic, wood block is still the best pavement for London. It is interesting to note that no hardwood blocks were laid in London during 1923. Brick Pavements. Many brick pavements have been laid in the cities in the United States, but very little of this type of work has been put down on highways. As the best practice is to lay the bricks on a concrete base, the cost is very high, and there would seem to be little reason for the adoption of the type in New Zealand. They are preferred in America on comparatively steep grades, as their surface is less slippery than sheet asphalt or concrete. In some places they have worn very unevenly, on account of varying hardness of the bricks. Rubber Roads. Small sections of rubber pavement have been laid down in England during the past few years. I made a close inspection of a section which had been down for seven months. It is situated around the cenotaph in London, and is 50 yards in length. The rubber blocks are approximately the size of ordinary wood blocks, and are made of two different kinds of rubber, the lower portion being hard and unyielding, and the upper thinner layer being quite resilient. The blocks are laid on concrete, and are interlocked. The most noticeable feature of the pavement is the very large distance it has crept in the direction of the traffic, the maximum movement being about 4 ft., which amount has been apparently taken up by compression. The pavement has needed constant attention. The wearing surface of the blocks do not show the slightest sign of wear, but on several occasions the blocks have bulged up over small areas. I was told by the foreman making repairs that when water finds its way down to the concrete the movement of the blocks under traffic in places caused them, to wear depressions in the concrete. The foreman also considered the lugs on the blocks required for interlocking to be impracticable when it came to repairs. The experiment certainly cannot be classed as a success. The cost of the pavement is said to be £4 per square yard. Rubber slabs, 9 ft. by 4 ft. 6 in., anchored to a concrete base, with steel cone rings, have recently been laid in other places in England, but I did not have the opportunity of seeing them. Guard-rails. The use of guard-rails of varying design is exceedingly common on the main highways of the United States. They are often used in places which to the colonial eye seem reasonably safe without such a precaution. In some places every embankment is provided with guard-rails. Various combinations of timber, concrete, and wire rope are used in their construction. Many of the rails erected in the past are far too light and offer only a moral protection to a vehicle, but the later and more elaborate types are strong, substantial affairs. The centre of the top rail is usually only about 2 ft. above the ground. A modern timber guard-rail consists of 8 in. by 8 in. posts, at about 7 ft. centres with a 6 in. by 6 in. rail. Concrete posts with timber rails is a common form of construction. A wire-ropo guardrail consists of timber or concrete posts strung with two f in. diameter galvanized-steel wire ropes. Tho ropes are provided with turnbucklcs, and are anchored every few hundred feet. I think this type is superior to the timber or concrete rail. In some places where rails cannot bo afforded large boulders painted white are placed at small intervals along the edge of tho embankment. Safety-devices and Warnino Signs on Highways. The most effective warning-device used in America for railway-crossings is what is colloquially called the " wig-wag " signal. It consists of a red disc on an arm which is electrically operated by an approaching train and swings with a pendulum motion. It is mounted on a post in a position that will catch the eye of the approaching traveller. At every swing the arm also strikes a gong. For night use tho disc is fitted with a rod light. At many crossings fearsome posters depicting imminent collisions aro affixed to posts. At one crossing I saw the remains of a motor-car which had. been practically demolished by a locomotive set up on a platform in a prominent position as a warning. For some railway-crossings in the north of Italy largo skull and cross-bones signs aro used. At sharp curves on concrete or other good pavements in the United States it is customary to paint white lines elong tho centre of the pavement. Those have an excellent effect in defining the limits of passing traffic. Under overbridges and other similar structures where visibility is poor a concrete kerb is often placed along the centre of the road for a certain length to guide the traffic and prevent collisions. In some places concrete shoulders and tree-trunks are whitened to assist tho motorist at night. Large mirrors are occasionally used, both in England and America, at important road-junctions to show approaching traffic. Cast-iron " buttons " set in the roadway are very much used to define turning-points at junctions, and some are fitted with lighting-devices for night work.