She was conscious of no feeling of astonishment. At every turn she seemed to be brought into contact with the central figures of the Corner House tragedy. A sudden inspiration came to her.
Although a system but recently developed, the employment of hydraulic machinery for transmitting and applying power has reached an extended application to a variety of purposes, and gives promise of a still more extensive use in future. Considered as a means of transmitting regularly a constant amount [54] of power, water apparatus is more expensive and inferior in many respects to belts or shafts, and its use must be traced to some special principle involved which adapts hydraulic apparatus to the performance of certain duties. This principle will be found to consist in storing up power in such a manner that it may be used with great force at intervals; and secondly, in the facilities afforded for multiplying force by such simple mechanism as pumps. An engine of ten-horse-power, connected with machinery by hydraulic apparatus, may provide for a force equal to one hundred horse-power for one-tenth part of the time, the power being stored up by accumulators in the interval; or in other words, the motive power acting continuously can be accumulated and applied at intervals as it may be required for raising weights, operating punches, compressive forging, or other work of an intermittent character. Hydraulic machinery employed for such purposes is more simple and inexpensive than gearing and shafts, especially in the application of a great force acting for a considerable distance, and where a cylinder and piston represent a degree of strength which could not be attained with twice the amount of detail, if gearing, screws, levers, or other devices were employed instead.The unhappy man bowed his head trembling,247 and with dull resignation he left the office, strongly escorted.
Cutting tools include nearly all that are employed in finishing; lathes, planing machines, drilling and boring machines, shaping, slotting and milling machines, come within this class. The machines named make up what are called standard tools, such [120]as are essential and are employed in all establishments where general machine manufacture is carried on. Such machines are constructed upon principles substantially the same in all countries, and have settled into a tolerably uniform arrangement of movements and parts.Here, as elsewhere, we shall employ the genetic method of investigation. Aristotles writings do not, indeed, present that gradual development of ideas which makes the Platonic Dialogues so interesting. Still they exhibit traces of such a development, and the most important among them seems to have been compiled from notes taken by the philosopher before his conclusions were definitely reasoned out, or worked up into a consistent whole. It is this fragmentary collection which, from having been placed by some unknown editor after the Physics, has received a name still associated with every kind of speculation that cannot be tested by a direct or indirect appeal to the evidence of external sense.
