In order to estimate the effect on the water level of the Chenab--below its junction with the Jhelum--it was necessary to observe discharges of the river, not only in the winter when it is low, but in the summer when it is high. The depth of the water was in some places 40 feet, and the stream 2,000 feet wide. Fortunately the Subdivisional Officer was a native of India and did not much mind the sun. A discharge curve (_River and Canal Engineering_, Chapter III. Art. 5,) having been prepared, it was possible to construct a diagram with periods of time as the abscissas, the ordinates representing the average known gauge readings on the different dates and another set of ordinates representing the probable discharges. By deducting the discharges which it was intended that the new perennial canals should draw off, it was possible to draw fresh ordinates representing the diminished river discharges and the reduced river gauge readings corresponding to them. It was found that the water level would be lowered by about 1·3 feet in April and May, and by about 1·5 feet in September. It was, however, shown that by shifting the heads of the inundation canals upstream--the gradients of the canals being flatter than that of the river--the effect of the lowering of the water level could, as heretofore, be nullified. CHAPTER V. PROPOSED IMPROVEMENTS IN IRRIGATION CANALS. 1. =Preliminary Remarks.=--The chief improvements which have been under consideration during recent years are three in number. The first is increased economy of water in its actual use in the fields; the second is reduction of the losses by absorption in the channels; and the third is distribution by means of modules.