The news item about a proposed railway system, linking London with Singapore via Lahore makes exciting reading. The idea is bold and imaginative and is in line with the current trend of globalisation in trade and economy and of easy movement of people from one region to another. I am sure the sponsors of the proposal must have taken into account its economic, operational and technical feasibility besides the socio-political constraints and activities of terrorists and militant groups in some parts along the route of the railway line. An important factor pertaining to the technical aspect of the proposal is the gauge of the track. At present, the following gauges are in vogue: the standard gauge in Europe, broad gauge in Pakistan and India and metre gauge in Bangladesh, Thailand and Malaysia. In order to avoid transhipment of freight and passengers, a uniform gauge throughout the proposed route would be necessary. It is difficult, though not impossible, to do this. More difficult would be the problem of integrating the new gauge into the rest of the railway network in the respective countries. -DANISH HASAN, via e-mail, April 29.