Show Volume of Niaara FalU The amount of water pawing I over Niagara falls varies wlui the height of the river Prof W r Gunning estimates the average amount at 15000000 cubic feet per minute Allowing 621 pounds pr the cubic foot this would total ti give a ttal of 5C2 JOOtona per minute or 2 I2MO tons In ii minutes of which somewhat some-what more than twothirds wbt wotln passes ps over tbo Horseshoe fall Other estimates place the total amount passing over both falls as high as 101000000 tons per ltour1r |