The following plan of filing and setting a cross-cut saw is original, I believe, and may be of use to some of your readers. From the saw, as commonly used, remove every third tooth, file the side of each tooth next this space, perpendicular, the back at an angle of 45 ; set the first two fronting on open space on one side, the next two on the other, alter nately. The saw is now like a cross-cut ten on saw except that it cuts both ways, with the advantage that one half of the teeth pre vent the other half from griping; it runs smooth and cuts fast. Since reading your remarks on the water power ot Niagara Falls, I would suggest the lollowing idea :—suppose the erfction on the bank ol the river ot one of Parker's latest pa tent direct-action water wheels, and also the erection of a range of factories a mile in length j an iron penstock 5 feet in diameter an inch thick, hooped with forge iron an inch thick, would bear 200 feet head (L30 would be all that would be needed) ; from a drum 12 teet in diameter on the shaft of said wheel, through said range of factories, over another of the same size, let there be placed (its weight properly supported) a wire rope or band an inch and an eighth in diameter, which would be slower than the working speed of the sunace jf the drum on said wheel; this rope, under a strain of 10 tons (it is said that it will bear thirty tons dead weight) would transmit 625 horse-power to the whole range of factories. This plan carried out would al low, notwithstanding its concentration, a vast amount of the water-power of Niagara Falls, to be applied usefully and economically. Hackettstown, N. J. C. J. D. In the Sandwich Islands they are turning i their attention to the giowth of wool.