When the battery is situated very near the object assailed, and it is desired that the shells may fall upon the magazines of the besieged. It is evident that projectiles the higher they are thrown up acquire more velocity in falling, besides striking the object more directly and with increased violence.
23. Under what angle are stone-mortars usually fired?
Under an angle of 60°, and sometimes of 75°, that in falling from a great height, the stones may have the maximum force of percussion.
24. Under what angle should grenades be thrown from stone-mortars?
About 33°; otherwise they will be buried in the earth, and their fragments will not be sufficiently destructive.
25. When a gun or howitzer is aimed with the line of metal horizontal, what is the elevation equal to?
The natural angle of sight or dispart.
26. How is the time of flight for siege mortars at an elevation of 45° determined?
It is nearly equal to the square root of the range in feet divided by four.
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