1832.] Comparison of the Indus and Ganges Rivers. I 21 



" In the middle of April, I found the Indus at Tatta to have a 

 breadth of 670 yards, and to be running with a velocity of 2^ miles 

 an hour. It happens, that the banks are steep on both sides of the river 

 in this part of its course, so that the soundings, which amount to fifteen 

 feet, are regular from shore" to shore, if we except a few yards on 

 either side, where the water is still. These data would give a discharge 

 of 1 10,500 cubic feet per second, but by Buat's equations, for the 

 diminished velocity of the stream near the bed, compared with that of 

 the surface, it would be decreased to 93,465 cubic feet; some further 

 deductions should be made for the diminished depth towards the 

 shores, and 80,000 cubic feet per second may be taken as a fair rate of 

 discharge for the Indus in the month of April. It is a source of regret 

 to me, that I am unable to extend my observations to the river during 

 the rainy season ; but I had not an opportunity of seeing it at that 

 period, and do not desire to place opinion in opposition to fact. I may 

 mention, however, that at Sehwan, where the Indus is 500 yards wide, 

 and 36 feet deep, and sweeping with great velocity the base of a rocky 

 buttress that juts in upon the stream, there is a mark on the precipice, 

 which indicates a rise of 12 feet during the inundations. This gives a 

 depth of 8 fathoms to this part of the Indus in the rainy season : if I 

 could add the increase of width on as sound data as I have given the 

 perpendicular rise or depth of water, we should be able to determine 

 the ratio between its discharge at the opposite seasons ; but I have only 

 the vague testimony of natives to guide me, and therefore dismiss 

 the subject. 



" From what has been above stated, it will be seen, that the Indus, 

 in discharging the enormous volume of 80,0C0 cubic feet of water in a 

 second, exceeds by four times the size of the Ganges in the dry season, 

 and nearly equals the great American river the Missisippi. The much 

 greater length of course in the Indus, the tortuous direction of itself 

 and its numerous tributaries, among towering and snowy mountains near 

 its source, that must always contribute vast quantities of water, might 

 have prepared us for this result ; and it is not extraordinary, when we 

 reflect on the wide area embraced by some of these minor rivers, and 

 the lofty and elevated position fiom which they take their rise: the 

 Sutlej in particular flows from the sacred lake of Manasarovara in 

 Tibet, 17,000 feet above the sea. The Indus traverses too a compa- 

 ratively barren and deserted country, thinly peopled and poorly culti- 

 vated ; while the Ganges expends its waters in irrigation, and blesses the 

 inhabitants of its banks with rich and exuberant crops. The Indus, 

 even in the season of inundation, is confined to its bed by steeper and 



