Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site wateng.UUCP
Path: utzoo!watmath!wateng!padpowell
From: padpowell@wateng.UUCP (PAD Powell)
Newsgroups: net.nlang.india,net.religion,net.philosophy
Subject: Re: Re: Re: Inquiry on Reincarnation (not again!)
Message-ID: <2482@wateng.UUCP>
Date: Thu, 6-Jun-85 14:00:36 EDT
Article-I.D.: wateng.2482
Posted: Thu Jun  6 14:00:36 1985
Date-Received: Fri, 7-Jun-85 02:23:31 EDT
References: <470@nmtvax.UUCP> <1289@amdcad.UUCP> <1899@ut-sally.UUCP>
Reply-To: padpowell@wateng.UUCP (PAD Powell)
Distribution: net
Organization: U of Waterloo, Ontario
Lines: 68
Xref: watmath net.nlang.india:407 net.religion:7049 net.philosophy:1872
Summary: 

In article <224@rti-sel.UUCP> wfi@rti-sel.UUCP (William Ingogly) writes:
>In article <1701@aecom.UUCP> version B 2.10.2 9/18/84; site rti-sel.UUCP version B 2.10.2 9/5/84; site aecom.UUCP rti-sel!mcnc!philabs!aecom!teitz teitz@aecom.UUCP (Eliyahu Teitz) writes:
>  
>>> > ...I have seen, with my very own eyes, along with many others,
>>> > people perform what is called a soft break. The idea is that rather
>>> > than breaking a 1.5 inch cinder block with brute force, the person
>>> > breaking the  block concentrates his energy in his hand, and with a
>>> > light tap breaks the block. 
>>> 

I do a fair amount of brick and rock work, and can verify that cracking a
brick is a fairly simple task.

Firstly,  bricks are fired clay, and usually have very high compressive
strength, and very little tensile (stretching) strength.   Additionally,
they are brittle, which means that they "snap" rather than "stretch"
as they are "stressed".

One of the problems of bricklaying is that bricks are one size.  If you need
a short one, you have to crack it.  To do so,  you pick up a brick, hold it
at one end,  take your mason's hammer,  and "clip" it with the blade.  Voila!
the brick, she breaks.

Now when I started out,  I would have to slam the *&^$^^# brick a couple of
times, and the cracks were really ragged.  I asked the guys who I was working
with/for how they did it.  I watched for a while,  and I came to the following
conclusions:
1.  The middle of the brick is under a compressive stress, the outside is
	in a tensile stress.  This is due to the way bricks are made: they cool
	down, outside cools faster than inside.
2.  The "grain" in bricks runs across the face.  This is because the material
	is forced into the brick moulds from the top, creating a layer.

------------------
| | | | | | | | ||
| | | | | | | | ||
------------------

       ^
	Hit here

3.  You hit in the middle of this stressed area,  and release one side.
	The crack will propagate through to the other.

Based on this model,  I surmised that the idea was to start a crack wide
	enough to go across the face,  and deep enough to go through the tensile
	stress layer.

Look at a mason's hammer some time.  The blade is about 1/3 to 1/2 of a brick
width,  with a even FLAT edge, slightly beveled at about 45 degrees.  It is
not a long blade, and is has its mass evenly distributed.  This makes it easy
to strike evenly across a brick.   In addition, look at how a mason will
tap a brick.   FLICK!! FLICK!!  The first tap will crack the top layer,
the next will extend the crack.   If you have wrists like iron, instead
of my wimpy silly putty, you almost always can do it in 1 blow.

How the %^&*% do those %^*^% do it with their hands?  The idea is to concentrate
the force in a line across the brick, with a very narrow "strike" zone.
If you have a very flat edge on your hand (which I don't!!),  and a heavy
callous (which most of the people in karate seem to have),  then you
have the conditions set up correctly.  All it would take after that would
be the convictions that you can do it,  and a pre-paid medical plan.

I might add that I still think the people who do it with their hands are
^&*((&^&*( maniacs...

Patrick ("Hey, gimme some more &))*&*()& mortar, and *()__(**() hurry up")
	Powell