TREES AND EXPLOSIVES.

Otago Witness, Issue 3098, 30 July 1913, Page 17

TREES AND EXPLOSIVES.

At the invitation of the Director of Agriculture (Mr A. H. Benson) a number of the delegates attending the Agricultural Conference hold at Devonport, Tasmania, visited the State farm on July 11, The first thing to engage attention was a demonstration in removing trees by the use of explosives. One of the delegates (Mr P. \V. Ke 11away, of Adventure Bay, Bruny Island, Southern Tasmania), who is an expert in the use of explosives, assisted by Mr J. Spcddy, were tire operators. Rackarock was the explosive used, and a large tree of about 4ft bin diameter was attacked. Five holes about sft in depth were bored around the forest giant at the points of greatest resistance, and theso were charged with rackarock, a primer of gelignite being utilised. None of the roots was cut, nor was an opening of any kind made, the demonstrator preferring ■ to show the means of removing such bur- ' dons to the land at a minimum of cost and labour. Those capable of judging estimated that the removal of a tree of tho kind, with its large roots, by ordinary moans would entail an expenditure of between £2 and £2 10s. A charge costing about 11s was used, and this was fired by means of a small electric battery. After connecting the charge by cable with tho battery a sharp plunge of a smgll handle was made, a loud explosion followed, and the largo tree was lifted bodily, twisted round, and camo down with a heavy crash. The demonstration was a marked success, the roots being loosened and drawn to such ; an extent as to make their removal one of little difficulty. The delegates expressed surprise at tho thoroughness of the operation.