374 
MINUTES OE PROCEEDINGS OP 
cartridge about to be used; he runs up the slider until its upper edge 
coincides with the division marked with the figures of the range in hundreds 
of yards; when using the scales on the front of the tangent sight, he slides 
the traversing bar to the left until the corresponding division on the drift- 
scale is visible at the left edge of the sight bar. The slider and traversing 
bar being thus adjusted to give the correct elevation and allowance for 
drift, the tangent sight is placed on the flat of the breech, when the divisions 
on the front are used; the sight is then taken over the upper V notch of 
the traversing bar and over the muzzle V notch directly on the object. 
These three points are brought into a straight line by working the elevating 
screw and traversing the trail sideways. 
When the scales on the rear of the tangent scale are used, the foot of 
the scale is adjusted into the groove of the breech and the sight is taken 
over the upper V notch of the traversing bar and over the trunnion sight. 
The following rules are to be observed in laying the gun at various 
ranges 
(a) In firing case shot up to 166 yards inclusive, the sight is taken by line-of- 
metal. At 250 yards the slider is run down to the foot of the scale and the sight 
taken over the upper V notch of the traversing bar. 
(5) In firing common shells at low angles up to and under 166 yards the sight 
is taken by line-of-metal. Between 166 and 250 yards the lower edge of the 
slider is brought in line with the division so marked and the sight taken through 
the lower V notch of the traversing bar. At ranges between 330 and 2499 yards 
the upper edge of the slider is brought in line with the appropriate division of the 
tangent scale, the sight being taken over the V notch on the upper arm. The 
divisions on the front of the scale are applicable to ranges up to 1660 yards, and 
from thence up to 2490 yards those on the back of the scale. 
( c ) In firing common shells at high angles the sight is always taken by tangent 
scale; from 420 up to 910 yards the scales on the front side are used; from 910 
to 1490 those on the rear side are employed, the upper edge of the slider is 
brought to the appropriate division and the sight taken over the upper v notch of 
the traversing bar. 
(d) In firing shrapnel shells at low angles from 250 to 1250 yards the divisions 
on the front side of the tangent scale are used; in this case the slider is invariably 
placed with its upper edge coinciding with the appropriate division of the tangent 
scale, and the sight taken over the upper notch of the traversing bar. 
(e) The drift scales are used as previously described. 
Laying on moving objects. 
19. The rules above detailed refer to laying a gun when the object fired 
at is motionless. 
If, however, the object is in motion, the method of laying must be some¬ 
what modified* 
If the object aimed at is advancing towards the gun, the gun should be 
laid lower than when the object is at rest; if the object is retreating from 
the gun> the gun should be laid higher ; in other words, the elevation should 
