18 1: 1.1 Wood's Report on the River Indus. 543 



nished once in seven minutes : with coal, (not however of a very good 

 quality,) every fifteen. Coal has thus an advantage over wood fuel 

 in something more than the proportion of two to one, and when the 

 superior performance of machinery driven by the former is taken into 

 account, it is doubtful which is the more economical plan to navigate 

 the Indus, with coal from England, or the jungle now growing upon its 

 banks.* The question resolves itself simply into one of expence, for 

 there is wood enough on the banks of the Indus, to keep two or more 

 steamers constantly plying for years to come. 



On this subject. Captain Johnston, the Controller of Government 

 Steam Vessels, has made several experiments with steam boats on the 

 Ganges. The result is already before Government ; but having obtained, 

 through the kindness of that officer, a copy of his report, the nature and 

 value of its contents is my apology for introducing it here. 



Report on the relative value of Wood and Coal, by Captain Johnston^ 

 the Controller of Government Steam Vessels. 



On Friday the 27th instant, I ordered the steam to be got up on 

 board the Experiment Flat, and ran for two hours on the ebb tide be- 

 tween Fort William and the Reach below Budgebudge, and consumed 

 nine and half maunds of coal, making on an average 29 revolutions. I 

 then returned with a flood tide, and in two hours consumed 1 1 J maunds 

 of wood, making on an average 21 revolutions. I also noted the time 

 we were running the same distances under coal and wood steam ; the 

 periods were 90 minutes with coal, and 112 with wood; great care 

 and persevering attention were required in the stocking with wood 

 to keep the steam up, and twice the engines were nearly at rest from 

 the steam failing. Admitting that the revolutions of the wheel on the 

 strokes of the piston in the cylinder measure the steam expanded in 



any given time, the coal would have supplied the cylinder 6960 times. 

 The wood, 5040 



Making a difference of ... ... 1920 



* Coal has been discovered on both banks of the Indus; the locality is the salt range, 

 in the parallel of 32o North, deposits extending in a longitudinal direction ; but not in 

 a North and South one. Ten specimens from the West bank procured by Captain 

 Burnes have been analized by Mr. Prinsep, and four of them pronounced to be the 

 purest form of mineral coal. Those forwarded by me, and discovered on the East bank, 

 have not yet been examined. 



