346 
MINUTES OF PROCEEDINGS OF 
The first thing we have to do is to calculate our muzzle velocity, 
which will be the same (or very nearly so) in each case, since the 
charge and brand of powder are the same. We have, in the first case, 
a series of observations, comprising ten rounds, where the effect of the 
wind is practically nil } and therefore we will select this case to give us 
the muzzle velocity. 
log — .= 9-7531, * 
w 
t — =3*851 secs, (reduced time), 
d 2 
range x secant 5° 3' x — = 3952 ft. (reduced range). 
Let us try 1300 f.s. first for the velocity. Opposite 1300 in Table IX. 
is 1*258 secs. 
1*258 + 3*851 = 5*109. 
Opposite 5*109 we find 896*6 as the remaining velocity. 
Turning to Table VIII., opposite 1300 we have 1865. 
1865 + 3952 = 5817. 
Opposite 5817 we find 899*1 as the remaining velocity. Thus our 
velocity has diminished more rapidly in the time travelled than in the 
space travelled. This shows that we have taken our velocity too high. 
Let us try 1274 as the muzzle velocity. Proceeding as before, we 
shall find that each table gives 891*6 as the final velocity; which shows 
1274 to be correct. 
This method of approximation comes out much more readily, after 
a little practice, than would be at first supposed, and is, I believe, 
exceedingly accurate.* 
Sir Henry James, R.E., in his work on meteorology, gives the 
following notation for the velocity of the wind :— 
f.s. 
1 = 7-071 miles per hour = 10*37 
2 = 14*142 „ = 20*74 
3 = 21*213 „ =31*11 
4 = 28*284 „ = 41*48, &c., &c., 
and this notation is, I believe, used at Shoeburyness. 
Employing these data to correct the other observations in the table 
of practice, with regard to the wind, we have in the second series, 
comprising four rounds, a wind directly in favour of the projectile. 
.*. cos D = 1, 
/Fcos H = 10*21 f.s., 
F — W cos E = 1263*79. 
* I hope that Professor Bashfortli will pardon me for thus using his tables. My apology must 
he that I have found them very useful in this manner, as well as in the determination of the effect 
of the wind on the range. 
