444 



TRANSACTIONS OF THE AMERICAN INSTITUTE. 



neck K of the cascabel, so as to allow the vertical rod G, which supports 

 the sight, to slide up and down therein. / is a horizontal slot formed 



therein, and J" is a wedge 

 provided with a stop j, and a 

 suitable knob or handle J"^. 

 This wedge is adapted to 

 release or tightly to confine 

 the vertical rod G, according 

 as it is moved from the right 

 to the left; and in case it 

 should, by any accident, be 

 lost or deranged, a piece of 

 tapering metal, or wood of any 

 kind, may be temporarily in- 

 serted to supply its place. This is important, because the usual way of fasten- 

 ing with thumb-screw runs the risk of the thread being stripped, and in 

 such case a thumb-screw is not easily replaced. The vertical rod G is 

 graduated so as to indicate the elevations of sight in seconds and parts of 

 seconds, and thus to indicate the time in seconds which a projectile will fly 

 at that elevation, and descend to the line of sight. My graduations are 

 adapted for service charges, and when less or more powder is used, or 

 slower or quicker burning powder is employed, allowance must be made 

 therefor; but with service charges of the proper powder the graduations 

 may be relied upon as giving, very accurately, the elevation required for 

 the rear sight in order to hit the object aimed at, provided the time of the 

 flight of the projectile is determined with accuracy. By this method, the 

 operation of adjusting the sights and the fuses, so as to explode shells at 

 given varying points, is very much simplified. The wedge J and its con- 

 nections allow the sight to be adjusted very delicately, and to be secured 

 firmly and quickly. For higher elevations than the light rod G admits, 

 wooden sights are supplied, as shown, which are inserted in the elevating 

 screw, which latter is hollow in the line of its axis; the wooden rods being 

 nicely fitted, will be held in their respective positions by friction. 



The front sights are denoted by M; they are shielded by a small ring N, 

 as represented, and are mounted by a very finely threaded screw 0, on a 

 thin ring P. This ring may be applied and removed from the muzzle of the 

 gun by turning the set screw Q, and it may be applied very accurately to 

 the muzzle of the gun, by the use of proper marks on each. This insures 

 that the front sights shall be always correctly in line. The ring P with its 

 attachments may be removed with great facility in case a gun is likely to 

 be lost, and be again quickly applied if the gun is retaken. 



THE WHEELS. 



The . purpose of this portion of my plan has been, to provide for the 

 shrinking of the wood and the stretching of the tire, by changing the posi- 

 tion of the parts of the wheel, so as to maintain a firm and rigid wheel 

 under all conditions; and, also, to allow of the easy removal and replacing 

 of all parts of a wheel without delay, and without removing the wheels 

 from the carriage. 



