Steam power, lor manufacturing purposes, is fast supplanting that of water in many places. Some years ago it would have been thought insane, in a business point of view, fc propose a steam engine for driving the machinery of almost any factory. Neither a cotton nor woolen manufactory, it was believed, could be carried on but by the side of some river or creek, where there was an abundance of wa ter and a good fall, to drive a water wheel. This is the reason why we find all the large old factories in our country established on sites commanding great water power. Some of these, too, are situated in exceedingly in convenient localities, so far as it relates to car rying the raw materials to, and the manufac tured products from them. The greatest ma nufacturing district in the State of New York, is perhaps the Valley of Saquoit, Oneida Co.; the creek bearing this name is studded with factories, and its waters are the hardest wrought of any in our land. This valley is two hundred and twenty-five miles from the sea-board and market—the raw materials have all to be carried up that distance and back again to New York City, involving an immense amount of carriage outlay. The fac tories in Massachusetts, and some other States, (at least many of them), are also situated far in the interior; thus there are quite a num ber situated in the mountainous district of Berkshire, near Pittsfield, and there are some away over the Green Mountains, in Vermont. Water privileges, at one time, were great ob jects of speculation, and water power is no doubt the most economical, in itself, but steam power has greatly reduced the estimation in which water privileges were once held, for in many respects it is superior, hence its domain is spreading far and wide, especially near the great marts of American commerce. One of the largest flouring companies of Rochester, N. Y.—a place distinguished for its water power and mills for grinding—is about to eom* mence manufacturing flour by steam within a mile of New York City. The business is to be conducted on an extensive scale, and if it were not more economical to use steam than water power this project would certainly ne ver have been undertaken; the projectors have no doubt counted the cost. To them, un doubtedly, the success of other steam flouring mills in this city has afforded a practical de monstration of the economy of steam power in comparison with water, eren when the raw materials are furnished from the very districts in which the Rochester Mills are es tablished. In making these remarks we do not wish to be understood as advocating a removal of manufacturing establishments from rural dis tricts to great business marts, and the entire substitution ol steam for water power in dri ving machinery; many reasons might be giv en by us to show the superiority of rural ma nufacturing villages ever pent up manufactu ring cities j our object is to direct attention to what is called " economical prime movers." Water power is undoubtedly much cheaper than steam power ; a wheel is cheaper than a steam engine : it consumes no coal and does not require the constant attendance of an en gineer or fireman, and yet we find some ma nufacturing companies substituting steam for their water power. Economy of fuel has re cently exercised a wonderful amount of phi lanthropic inquiry and excitement, in order to find a cheap substitute for the steam engine, and yet we find shrewd business men adopt ing the steam engine with all its expense of fuel, in place of a prime mover which con sumes no fuel at all. There must be some reason for this; and the natural conclusion is, that the economy of the steam engine has been fully established by its success in many manufactories which compete with those who use water power. But who has been count ing the cost of employing one kind of a steam engine for another to save fuel ; we have not heard a word about the saving of fuel that may be obtained in steam engines themselves. k jn the city of New York hundreds of tons of coal are puffed into the air every day, and this with such an apparent easy carelessness, as il to say, " the saving of fuel is not the only thing we care about." The great majority of steam engines in our cities are high pressure and non-condensing. The same power could be obtained with one halt the expense of fuel, if larger engines, supplied with steam genera ted under a high pressure, using it expansive ly and then condensing it, were employed in stead of the small high pressure engines. We know that we are rather under-stating than over-stating the economy of fuel that would be obtained by such a change j still we could not expect to see such a change generally adopted,for other questions of economy are em braced under this leading one. Thus, a larger amount of space would be required for machi nery, and a greater expense for the engine, and then a great expense would be entailed for condensing water. The economy of fuel, therefore, is not the only expense to which manufacturers look, or to which their atten tion should be exclusively directed;, "all things must be taken into consideration," and the profit and loss of each carefully estima ted. In places near large commercial cities, every manufacturing company that has a quar ter of an acre of land attached to their facto ry, should never use a high pressure non-con densing engine. A pond can easily be con structed beside the iactory to contain the w,a-ter for supplying the boilers and the hot well —this water can be obtained from the roof of the lactory, and it can be used over and over again for fifty years. At the present time we know there are hundreds of establishments in our land, which, in the aggregate, recklessly throw thousands of tons of coal away into the atmosphere, every day, in the form of com pressed steam. This may be the case in some establishments, where the proprietors are con tinually grumbling about the expense of fuel. We beseech those men to look well into their own interests, and not over them, before they speak evil again, respecting the expense of steam power. We are perfectly satisfied that there is a general and daring waste of steam power, which can be saved to our country, and we hope that what we have said will be the litSins o Hree*msHjke"itttenMoK of all those engaged in manufacturing operations, to this important question, viz., the saving of fuel in the steam engine, according to the knowledge which all engineers possess res pecting it.