Evening star. [volume] (Washington, D.C.) 1854-1972, 1926-08-15
12,0)0,0)0,O0O CELLS
IN SKIN OF HUMAN
Microscopic Units Similar to
Building BIocks-Fit Com
pactly Together.
By DIR. EDWIN e. SLOSSON,

1
| Director Science Service.
| All plants and animals are con-
| structed out of little building blocks
of a very similar sort. Each block is
a cell, which, when fresh and living,
| consists Of a tiny drop Of jellied sap
| or juice inclosed in a thin-walled sac
| When a thin slice of any vegetable or
| animal matter is cut and put under a
| microscope, the individual cells can
be seen. When free and separate they
are round. When compressed to-
| gether in a mass they form various
fiat sided figures, mostly of four, five
| or six sides.
| This suggests two questions. Why
| are the free cells round? What shape
| are the maSSed cells?
| The answer to both questions Is the
same. The cells in both cases take
| the shape that will comprise the most
| substance in the smallest space. 1t is
| an instance of natures economy: an
| effort to make the cell-Wall stuff go as
| far as possible.
Follow Least Resistance.
| 1t is easy to see why cells are
| spherical whenever they can be. They
| take that shape for the same reason
| as bubble or q. balloon. They
| just blow it up and it takes the shape
| that will hold the gas or hot air with
| the least stretching of the inclOSinG
| film. Put a lot Of irregular fragments
of marble into a barrel, attach the
| barrel to a water wheel SO 1t will be
| kept rolling.
BY and by it will be found that all
| the pieces of rock, however angular
| and knobby they may have been on
| the start, have been ground into the
! same form, a sphere. BY rubbing
| against one another all their angles
and prominenceS have been knocked
off, and when one knocks off all the
corners and projections from anything
| they have sphere. The pebbles and
sand grains on a SeaShOre have been
ground down by friction into the same
| shape, which is the form that in
! cludeS the largest amount OF material
| with the smallest surface.
| But when q person masses the cells,
| they get different and more difficult
| problem, one in fact that has been
| a. puzzle for more than hundred
and fifty years. For when in pack
| ing together a lot of spheres, say shot,
or oranges in a box, they do not fit
| together but leave waste space in
| between them. Each sphere, except
I those on the outside layer, is in touch
| with twelve others. This can be dem
onstrated by putting a pea on the
table top 1t will be found that it
takes six others to form a ring around
| it. On top Of the group, one can set
| three others. and of course three more
could find place below it. If, then
| a bunch of spheres should be com
| pressed, the - points of contact
| would become fiat faces, and when
! all the empty space was squeezed
out the interior spheres would all
| become 12-sided figures.
Experiment BY Frenchman.
Button, the great French naturalist
| # the eighteenth century, tried this eX-
pertinent by packing dry peas in a
| jar and then soaking them with water
| till they swelled tight together. EX-
| perimentS with masses of bubbles con
| firmed this 12-sided shape as an eco
nomical form. OF the II faces 6 are
| triangles and are hexagOns. The
| honeybee uses this fosm for it's comb.
! But Lord Kelvin, the great English
! physicist of the ninteenth ceneury.
| found that space could be filled com
| pactly and with less sacrifice of the
| spherical form by a more stable figure
| l4-sided figure. He has mapped and
now DIR. F. T. Lewis of Harvard
| Medical School, after many years of
I
| NAL cells generally tend to take this
| IA sided figure. He has mapped and
measured with the microscope con-
secutive sections of various tissues.
| such as elder pith and human fat and
| then constructed large wax models OF
| the cells that would account for the OBJ
| served contacts. They are very If
regular and differ in the number OF
| their flat faces because they get dis
torted by the pressure of their selfish
| neighbors, but can be best regarded
| as all derived from this fundamental
| l4-sided form.
| Eight of it's faces are heXagons and
six are squares There are SO edges
| where two faces intersect and "a
! corners where three faces intersect.
| Such figures fit together as prettily
| as a Chinese puzzle, each in touch
with IA neighbours. 1t Is worth while
getting acquainted with it since 1t
is the pattern approached by the
| 10 900 million cells that constitute
the human skin. as well as incalcu-
liable myriad of it.