Carriage Insulation and Ventilation

An entirely new plan for sleeping car ventilation, recently employed by the London, Midland and Scottish Railway, is of interest (says our London Correspondent).

The new ventilation method is known as the “Punkah” system. Home railway sleeping-cars are constructed on the compartment principle, with a side corridor running the full length of the vehicle. In each sleeping compartment, just over the bed head, a patent louvre is fitted. At the same height as the louvres, an air duct runs along the whole length of the corridor, connection being made to the louvres by a hole cut in the corridor partition. A centrifugal fan, direct-coupled to a 250-watt electric motor, is placed on the top of a linen cupboard situated at one end of the corridor, the motor being energised from the ordinary lighting set. By means of a valve, air can either be delivered to the berths, or extracted therefrom. Air from outside is passed through an oil filter, and the volume of air entering a berth is controlled by the individual passenger, who may shut off the supply completely, or partially, according to his needs. Under stiff trials, the L. M. and S. Railway states that even when passing through the longest tunnels, smoke and fumes were not delivered to the compartments.

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