114 ANNUAL OF SCIENTIFIC DISCOVERY. 



bit against an iron bolt. If he wishes to bore for new treenails of a different 

 size from that which he has been using and boring for, he has but to unscrew 

 his bit and put on another of a different size on the same stock, to bore a 

 hole of a proper size. Scientific American. 



Improved Wood-Sawing Machine. Mr. A. "Winter, of Rondout, N. Y., has 

 recently patented a wood-sawing machine for railroad or other purposes, ca- 

 pable of sawing more rapidly and with much less attendance than usual, and 

 delivering the sawed material at any point desired. The wood may be sepa- 

 rated in two or more places at the same time by simply mounting several 

 saws upon the shaft ; and one machine on this plan now in use on the line 

 of the Reading Rail-road in Pennsylvania has proved itself capable of sawing 

 and throwing upon the pile a cord in four minutes. It may be driven by 

 either steam or horse-power, its principal peculiarity consisting in a series of belts 

 or endless chains, provided with suitable hooks which carry forward the sticks 

 at a moderate rate, present them to the action of the rapidly-revolving circu- 

 lar saw or saws, and then continue to carry them onward and drop them at 

 the point desired. The belts or chains may be of any length desired, and so 

 arranged as to elevate the wood to any required degree, the labor of the at- 

 tendants being reduced simply to that of laying on the wood. 



Machine for Sawing and Splitting Kindling Wood. This machine for sawing 

 and splitting kindling wood, invented by J. A. Conover of New York, is con- 

 structed as follows : At the rear of the machine there is a circular saw which 

 divides the sticks into suitable lengths, while at the front part there is a large 

 splitting-ax, having four blades arranged at angles. These are attached to a 

 vertical shaft, and move slowly up and down. Between the saw and the 

 splitters there is a strong .endless belt which receives the blocks of wood ends 

 up, conveys them along toward the front till they come beneath the splitters. 

 The stuff is here divided into kindling wood with great rapidity, and falls 

 down in a pile at the base of the machine. The splitters have a very stately 

 sort of movement, and when they enter the wood seem like spades acting on 

 the soil, handled by some monstrous giant. We are informed that a man is 

 enabled to cut up and split fifteen cords of wood per day with one of these 

 machines. Scientific American. 



Straining Saws by Atmospheric Pressure. Many attempts have been made 

 to dispense with, and so save the power required to drive, the cumbersome 

 sashes used in all saw-mills, by introducing an independent means of straining 

 the saw-blade. In some instances steam has been employed ; in others, air 

 cylinders have been placed at each end of the saw, to which pistons, traversing 

 the cylinders, were attached. The cylinders were exhausted by means of an 

 air-pump employed for that special purpose, and the saws thus strained be- 

 tween the pistons. In an improvement recently patented by Brown & Coffin 

 of Texas, the straining is accomplished in a similar manner, except that no 

 pump or extra gearing is involved. A flat valve, opening outwardly, is placed 

 in the bottom of each cylinder, which, by the alternate movement of its pis- 

 ton, opens and closes, thus producing the required exhaust or discharge. By 

 this simple means the saw-blade is at all times kept evenly strained, by a 

 yielding, self-adjusting pressure, which prevents the possibility of accident, 



