THE COAST ARTILLERY JOURNAL - Air Defense Artillery

268 THE COAST ARTILLERY JOURNAL
a. Four holes (equally spaced) are drilled and tapped through the rammer head
to receive No. 24 brass flat-head screws.
b. These set screws support a metal (preferably brass) ring through which a
double thicknkss of burlap, 24"x 23", is threaded the long edge parallel to the stave
and its mid point approximately % inch in rear of the rim of the rammer head. That
half of the b~rlap (B) in rear of the rammer head is now folded over the rammer head
(see figure 4).
3. The ring is now pushed against the rim of the rammer head and the set screws
screwed home (figure 5). The ring will now hold the front end of the sponge. The burlap
(A and B) .is now folded back over the rammer.
4. Cotton waste is now packed inside the burlap and around the rammer. When the
sponge is well packed and has a maximum circumference of 21 inches, the seam (parallel
to the stave) is sewed.
5. The open end is now wired to the rear of the rammer head. Any burlap in rear of
the turns of wire is folded back over the wire and sewed to the rear end of the sponge.
6. The iron stave is replaced with a wooden stave for ease in handling (figure 7).
7. The advantages of this rammer-sponge are:
a. A rammer similar to the above was made by the writer and used by Battery B,
92nd Coast Artillery (PS), in all practices this year and saved on an average of 3 seconds
per salvo.
b. The ramming and sponging were as good as if the separate units were used.
This was accomplished by using three men on the rammer-sponge. A test made in one
practice showed the density of loading to be equal for each trial shot.
c. This rammer-sponge is easier to handle than the rammer as issued, as it
weighs 13 pounds less after being dipped in water.
d. It has the advantage over any other rammer-sponge the writer has seen in that
.t will, with proper care, last at least an entire season. The wear and tear is taken up by
the front of the rammer head.
e. It will cost little to modify-
Ballistic Effects Due to the Rotation of the Earth
By HENRY B. HEDRICK, PH. D.
The transfer of the rotation of the earth to a parallel axis passing through the point 0,
occupied by the gun, is accomplished by reducing the point 0 to rest by applying to every
point under consideration an acceleration equal and opposite to that of 0, namely
ll'b where b is the distance of the point 0 from the axis of rotation, and also applying a
velocity equal and opposite to the initial velocity of 0, namely Qb. The whole figure will
then be turning about an axis 01, parallel to the axis of rotation of the earth, with an
angular velocity ll. It is ~his latter rotation which was resolved by the present writer into
the three components llx. lly, llz, on page X of the introduction to the 1924 Ballistic
Tables, namely;
(1) n,,, Q cos L cos A
where
~_llsinL
II _ Q cosLsinA
A = Azimuth of the plane of fire
L = Latitude of the position of the gUn