Page:Miscellaneous Papers on Mechanical Subjects.djvu/16

 8 Another evil of grinding is, that it takes from the mechanic all sense of responsibility, and all spirit of emulation, while it deludes him with the idea that the surface will be ultimately ground true. The natural consequence is, that he slurs it over, trusting to the effect of grinding, and well knowing that it will efface all evidence either of care or neglect on his part.

It thus appears that the practice of grinding has altogether impeded the progress of improvement. A true surface, instead of being in common use, is almost unknown. Few mechanics have any distinct knowledge of the method to be pursued for obtaining it, nor do practical men sufficiently advert, either to the immense importance, or to the comparative facility of the acquisition.

Due latitude must be allowed to the expression “true surface.” Absolute truth is confessedly unattainable. Moreover, it would be possible to aim at a degree of perfection beyond the necessity of the particular case, the difficulty of attaining which would more than counter-balance its advantage. But it is certain that the progress hitherto made falls far short of this practical limit, and that considerations of economy alone would carry improvement many