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132 Steamers on the canals at present are the inspection boats of the Public Works department. Mr. Walch1 says that: —

'The introduction of steam power for the transportation of freight along the canals has often been considered, and it has to some extent been tried without success. It cannot compete with manual labour unless that becomes far less plentiful and cheap than it now is, and unless canals along the chief lines of communication be maintained along their whole lengths and at all points to a depth greater than is now the case. That steam or perhaps electricity will eventually supersede towing coolies on the Gódávari canals is most probable, but this will not be for many a long day.'

The combination of irrigation and navigation in these canals is not entirely without its drawbacks. Their requirements are necessarily to some extent conflicting.

'For irrigation, large quantities of water and consequently of silt have to be taken into a canal, and therefore the slope of the surface must be considerable; for navigation the less water taken into the canal the better, and its surface should have no slope. For irrigation, there are times when the canal should be kept low so that large quantities of water may not have to be passed into the drainages when they are already filled by rain-water; for navigation the canal should always be kept up to its full level. For irrigation, even when the river or other source of supply is low, it is often necessary to go on letting as much water as possible out of the canal to supply crops, thereby reducing the level and the depth in the canal, especially at its end; for navigation at such times the water should be kept in the canal so as to maintain as nearly as possible its full depth.'

These difficulties have been experienced in the Gódávari system. On the Ellore canal, which is the through line of communication to the Kistna river system, the silting was found to impede traffic, and the necessity of keeping enough water in the canal for navigation caused much tempting extension of irrigation to be abandoned. These facts were adduced in 1888 as arguments for the necessity of lightening that canal of some of its traffic and in support of a proposal for a railway between the Kistna and Gódávari rivers — a proposal which has since developed into the North-east line of the Madras Railway. As far as the present district is concerned, navigation is always subordinated to irrigation, and though every attempt is made to keep the canals full, navigation has to take its chance when water is scarce. The only railway which traverses the district is that which was originally called the East Coast Railway but is now