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Some experimental sections of " drag-seal," which process has been developed to a high standard in Australia, have been laid. The Board is indebted to the Victorian Country Roads Board for particulars of this class of surfacing. Drag-seal work appears to remain somewhat open for a period after being laid, and as a consequence may not be entirely suitable in the colder districts of New Zealand, but where it is found to be satisfactory it will often serve a very useful purpose. Drag-seal surfacing is somewhat similar to " plant-mix" or " road-mix," except that open graded chips lying between J in. and § in. circular screen dimensions are used instead of the densely graded aggregate. The asphaltic binder is a kerosene type of cutback with a comparatively soft residue or base. In other words, a non-volatile heavy road-oil containing between 90 per cent, and 95 per cent, of 80/100 penetration asphalt is cutback with a kerosene distillate in the proportion of 10 per cent, to 15 per cent, of the total product. The chips and asphaltic binder are mixed together in a central plant or on the road, and then spread out to a true finish with long wheel-base graders, and rolled. After initial rolling, quarry grit or coarse sand is lightly spread over the surface to fill the voids. Further rolling and broom-dragging complete the work to a smooth riding finish. Special mixing and spreading machines have been developed in Australia, but so far in New Zealand this work has been accomplished with power-graders. Drag-seal will utilize chips which are unsuitable for the standard road-oil sealing, and which do not contain the necessary fines or filler for " plant-mix " or " road-mix." Another type of bituminous surfacing which has been developed in New Zealand, and is proving very satisfactory either as initial treatment on primed macadam or as a smoothing course on old waved and corrugated pavements, is what has been designated " emulsion broom-drag coat." This consists of a light-tack coat of quick-breaking emulsion, followed by an application of about | in. to f in. loose depth of clean \ in. chips (passing f in. or § in. circular screen and retained on f in. or \ in. circular screen) which are rolled, and then broom-dragged to a smooth and even surface. The chips are again thoroughly rolled, and, before any disturbance of the surface occurs, penetrated with quick-breaking emulsion so that the sum of the tack coat and the penetration coat is from 32 gallons to 36 gallons per cubic yard (loose) of chips with an emulsion containing from 52 per cent, to 55 per cent, of 200 penetration asphalt. Immediately following the second application of emulsion the surface is sanded and given a final roll. The emulsion broom-drag coat is very suitable for initial surfacing when the weather is unfavourable for hot bituminous work, and when clean but only wet chips are available. This type of surface can also be laid as a smoothing course without heavy graders and planers, but it may be possible to further improve the surface finish by blading the chips into position either with or without broom-dragging. Laboratory tests and road experiments are being conducted at the present time with a view to developing a cheap method of priming a gravel or macadam surface during the damp and cold winter months. The value of such a development will be obvious. The winter priming is required to hold the surface in good order until the summer, when the bituminous wearing-course can be applied. At the same time this priming coat must serve the functions of an ordinary tar primer when applied under suitable conditions. A type of road-mix with slow-setting emulsion has been laid with some degree of success, but the cost of such work precludes its general adoption. A rather novel experiment was conducted some while ago with the object of overcoming the numerous complaints against slippery longitudinal timber-planking on bridge decks. Ordinary wire netting of about 1J in. mesh with 16-gauge to 18-gauge wire was stretched and securely stapled along the wheel-tracks. This appears to have been completely successful in providing a durable non-skid surface. As far as possible advantage continues to be taken of the roading research and progress which is taking place overseas, but, unfortunately, much of the work as done in America and Europe, where different conditions prevail, is not applicable to New Zealand. While the Board is indebted largely to America, and especially the Bureau of Public Roads, for roading information, it has had to solve many of its own problems. The Board is pursuing with all energy a policy of research and investigation into the many roading problems which remain to be solved, with safer, better, and cheaper roads always as the objective. New Standard Specifications covering Formation, Preparation of Subgrade, Construction of Metal Crusts, Priming, and Road-oil Sealing have been recently distributed to the various roading authorities. An entirely separate specification for each class of work, covering a wider range of bituminous wearing-courses, together with various notes and instructions, are in course of preparation. These will be printed in the near future. Copies of the specifications will be available for inclusion in contract documents, while, in addition, the specifications, notes, and instructions will be bound together in loose-leaf form as general reference volumes. Operations of Magnetic Truck. The Board's magnetic truck, which is used for clearing main highways of iron or steel punctureproducing articles, has been in operation in the North Island during the year. The length of road actually cleared during the year ended 31st March, 1938, was 4,427 miles, as against 2,139 miles for the previous year, while the weight of material picked up by the magnet was 3,783 lb., as against 7,125 lb. for the previous year. The average yield per mile was 0-85 lb., the corresponding figure for 1936-37 being 3-3 lb.

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