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Use of Explosives During the year an approach was made to the Branch by the Post and Telegraph Department, which was considering the practicability of using explosives on certain of its works such as pole-setting, excavation of manholes, opening up trenches for cablelaying, &c. A short specialized course on the use of explosives was devised by the inspection staff of this Branch and trainees at the Post and Telegraph Department's school at Trentham were put through this course, which consisted of brief lectures on properties and methods of handling explosives, followed by a practical course in the field. Demonstrations of the various uses to which explosives could be put in the particular classes of work under consideration were given by Inspectors of the Branch, and the trainees were then required to carry out these operations under supervision so that they would acquire the necessary practical experience. On completion of the courses a comprehensive pamphlet of all features covered in the course was prepared. At the suggestion of the Department arrangements were also made for issuing certificates of proficiency to trainees who qualified in their course on explosives. One further interesting operation was conducted by the Branch at the. request of the Union Steam Ship Co. of New Zealand, Ltd. This was the sinking of an abandoned oil-hulk, the " Adderlev." In view of the closely compartmented construction of the vessel, the problem of sinking it was obviously a difficult one. What is believed to be a new technique so far as the sinking of hulks in New Zealand is concerned was adopted. This new procedure consisted in applying the charge on the outside of the ship well below water-line in place of the hitherto generally adopted method of laying the charges inside. The results demonstrated the efficacy of fixing the charge in this manner, and although the vessel took some time to settle down finally, this was not entirely unexpected, in view of the numerous watertight bulk-heads. Inspection Work This phase of the work is still well in arrears, for the reasons given in the previous annual report. However, with the acquisition of additional staff it is hoped to be able to make up a good deal of the leeway in the forthcoming year. Local Administration The number of local-body licensing authorities under the Explosive and Dangerous Goods Amendment Act, 1920, still stands at 163. As a result of suggestions made by some of the officers administering the Act within local-body areas, it has been decided to embark upon a new departure —viz., the holding in Wellington of a conference of local-body Inspectors from the major local-body licensing authorities. The response to inquiries by the Department amongst licensing authorities has been most encouraging and a very successful conference should result. Amendment of Legislation For some years past the Department has recognized that the existing regulations under the Explosive and Dangerous Goods Amendment Act, 1920, which were enacted in 1928, are no longer adequate, nor are they in conformity with technical advances in industrial developments. But for the intervention of the war the regulations would have been amended some years ago, and this matter has now become one of some urgency. One of the principal purposes of the Inspectors' conference mentioned above will be to discuss fully the existing problems and to formulate a basis for the pending amendments to the regulations.

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