MESSRS. EDITORS—Being an engineer, millwright and machinist, I am an interested reader of your able, high- minded, and interesting paper. I find it assumes to be no more than what it really is, a record of science and truth, and a fearless advocate of correct principles and valuable improvements. I am with you in exposing those apparent improvements which are tounded on imaginary theories, and those which are equally as fallacious which are founded upon incorrect estimates and experiments. By this course your journal becomes a valuable instructor and a" check to the wild ambition of some of the inventors and engineers of the present age. Some fearless guide—some correct standard—is needed as a beacon to warn the public against adopting too hastily the conclusions of many so-called scientific men. I hive been engaged for some time in putting up steam engines and circular saws, and I have taken the liberty to suggest an idea or two in relation to them; those I have constructed are of the kind manufactured by Hoe Co. A great amount of time and money has been expended to bring these saws to perfection, and those who have seen them in operation will acknowledge that they are not exceeded by any in use. It is true that the same sized saw will not cut as wide plank as one without a shaft, and constructed alter the manner of some of those lately patented, but in point of economy they must be qtoite superior ; many difficulties will, I think, suggest themselves in the use of the saws without a shaft or spindle. There is too much machinery and what is used is not applied to advantage—the saw is too liable to bend, tco liable to get out of repair, and does not work with th" force and strength of a common circular saw ; a fifty-four inch circular saw constructed after the plan of those manufactured by Hoe Co.— (and \ set no value upon those saws above others equally as efficacious) —will run six hundred revolutions per minute, cutting j three-quarters ot an inch to each revolution. It must, in order to accomplish this result, be put up in mechanical style, and furnished with the requisite amount of- power and attention. No water is required to keep it cool when running at this rate. E. A. F.