THE YOUNG SCIENTIST. 
63 
gusts of wind strike the top a little more 
forcibly, and it begins to duck. You will 
notice that at every sweep or circle the kite 
makes, it gets nearer to the ground, and it 
usually strikes about head foremost. This 
is - because when the head of the kite is 
moving on the downward side of the circles 
of its sweep, it does not feel the weight of 
the tail, and so moves very fast, while when 
it is sweeping with the top of the kite up- 
wards it has to pull the tail after it, so it 
comes down with a spiral movement like 
this (Fig. 4), the head of the kite always 
Fig. 4. 
pointing downward on one side of the cir- 
cles, as you see by the arrow, A, and always 
pointing upwards on the other side, as you 
see by the arrow, B. Now, if you notice, 
Harry, you will see that as the kite travels 
downwards on the A side, it must always 
strike the ground on its head or on its side. 
But your questions have rather led us away 
from the consideration of the shape of the 
.kite, though in answering them I have 
shown you that the best shape will be that 
which will keep the surface of the kite as 
near flat as possible, while whatever bag 
there may be shall be in a direction to lift 
the kite, for you will notice that the bag of 
the face of the kite will always be in the 
same place, no matter where the string is fas- 
tened to the belly-band. Here is a kite 
of the square kind (Fig. 5). You see from 
the shade upon its face that its frame is 
composed of two pieces of wood, crossed at 
the middle, and supporting the paper 
across corners, so the paper between the 
supports bags or bends to the force of the 
wind. Now, look at the division marked 1, 
and you will see that its bagging throws its 
surface slightly in the direction of that of 
the kite shown in Fig. 3, and so tends to 
keep the kite from flying so well as it would 
Fig. 5. 
do if the bag was not there. The directions 
of the bagging of the divisions 2, 3 and 4, 
do not act to stop the kite from rising." 
" What makes the face of the kite bag 
that way, Uncle?" 
Fig. 6. 
"Because the frame gives way to the 
force of the wind. In fact, Harry, it is a 
weak form of frame, depending only on the 
twine which ties it together to keep it in 
shape and stiff, and as the paper cannot be 
stretched tight on the frame, the bagging 
is sure to take place." 
** "Would a big square kite bag too?" 
