ENGINEERING
IN THE COBWEB
Have you ever noticed the shapes of spider webs? Did you
know that spiders produce their thread themselves and that this thread has
some amazing characteristics? Or have you heard that the techniques used
by garden spiders to spin a web are the same as those used by civil engi-
neers today?
A spider needs two separate places in order to spin its web. Webs are gen-
erally spun in a corner where two walls join or between two branches.
However, some spiders are so skilful that they spin their webs using a sin-
gle surface. How a spider spins its web is spectacular. Now try to visualize
what we will tell you here.
A spider first finds a flexible branch that is long enough to spin its web. It
firmly fastens a thread to the end of the branch. Walking down the branch,
it continues to secrete thread. Once it covers a certain distance, it stops and
ceases to secrete. It pulls the thread it has secreted until the branch is bent
like a bow. The spider sticks the other end of the thread, which
is now as straight as a string, firmly to that point. Then it
starts to spin its web inside this bow.
Now consider what you would do if you were to
stretch a string two and a half meters long
W O N D E R F U L C R E A T U R E S
47
