THE TUNNEL MISHAP

New Zealand Herald, Volume LXXII, Issue 22198, 27 August 1935, Page 13

THE TUNNEL MISHAP

Sir, —The travelling public are indebted to you for your timely editorial stressing the desirability of a fuller explanation from the railway authorities of the cause of the above mishap. It is hardly correct to say that there has never been a parallel case elsewhere, and the writer remembers a similar case where a troop train was gassed by locomotive fumes, many years ago in the famous Khojak Tunnel, in Baluchistan, India, owing to a combination of circumstances. In that instance a succession of troop trains had been passing through the tunnel itf'the same direction, and thus the last train, which had a strong wind following it, was enveloped in fumes as it passed through. Moreover, the Khojak Tunnel, like that at Poro-o-Tarao, is on the crest of a hill, with both entrances much lower than the apex at the centre of the tunnel. Thus a pocket is formed at the apex, which imprisons the hot carbon monoxide fumes from the locomotives, and this spot is a potential source of danger should a train for any reason be brought to a standstill when in the tunnel. The remedy is to provide a vortical ventilating shaft at the apex of the tunnel, to allow the imprisoned fumes to escape. Thomas A. F. Stone.