Solid Geometry Puzzles 107is just one of those practical problems with which the soldier is faced from
day to day when on active service. Important results may hang on the rider
taking the right or the wrong route.
SAND
*-~----------------~
Which way would you have gone? Of course, the turf and the sand extend
for miles to the right and the left with the same respective depths of three
miles and two miles, so there is no trick in the puzzle.
- THE SIX SUBMARINES
Readers may remember a puzzle,
to place five pennies so that every
penny shall touch every other penny,
that is given in my book, Amusements
in Mathematics, and a correspondent
has suggested that as many as six
coins can be placed under the condi-
tions if we arrange them as shown in
the upper diagram-that is, with A,
B, and C in the form of a triangle,
and D, E, and F respectively on the
top of A, B, and C. If we take a sec-
tion of the coins at XY (see the lower
F
C