THE EOYAL ARTILLERY INSTITUTION. 
321 
Now, corresponding to velocity 1420 in Table I. we find 
ft. 
1251-1 
Adding reduced range, 954*9 
2206-0 
which, by an inverse process in the same table, corresponds to a velo¬ 
city of 1240 f.s., nearly. 
Hence, striking velocity at 1000 yds., is 1240 ft. per second. 
(2) With what velocity would a 9-in. shell, fired under the above 
conditions, be travelling at the end of 3 secs. ? 
& 
Here, reduced time = t = *3183 x 3 secs. = *9549 secs. 
w 
Now, corresponding to velocity 1420 in Table II., we find 
see. 
•8057 
Adding reduced time, *9549 
1-7606 
which, by an inverse process in the same table, corresponds to a Velo¬ 
city of 1194 f.s., nearly. 
Hence, remaining velocity after 3 seconds* time of flight is about 
1194 ft. per second. 
(3) What would be the time of flight of a 9-in. shell, fired with a 
battering charge of pebble powder, over a range of 1000 yds. ? 
From example (1) we know that the remaining velocity at 1000 yds. 
= 1240 f.s.; so that the above question resolves itself to this:—In 
what time would the velocity of a 9-in. shell be reduced from 1420 to 
1240 f.s.? 
d? 
Here, reduced time — -t = -3183^. 
w 
Now, corresponding to velocity 1240 in Table II. we find 
sec. 
1-5285 
Ho., do., velocity 1420 -8057 
Subtracting, *7228 = reduced time . 
Hence, “3183^ = *7228, 
t — 2*27 secs. 
