One of my earliest memories of sifting sand comes from my childhood. I can still clearly recall how my brother would scoop a shovel of sand and make it “rain” through the makeshift sieve while the stones remained – most likely for one of my dad’s many projects.
There were great successes: The one-of-their-kind gardening tools that he could weld in the blink of an eye, the outbuilding that was transformed into a lovely, cool lapa retreat, the 3m high outside bread oven where he so expressively burnt himself one day …
The whole sifting thing came up again in my first year. Transport Engineering was not the most exciting subject, but at least I had a basic understanding of sieves and stone grading and how different sized stones were meant for different tasks.
Now, the practical classes of Construction were way more interesting. During our time in the labs we could mix concrete, cast it, and then let it cure before we measured its strength.
“Cement” is not something that comes from the earth. The bags that we buy from Builder’s is a mixture of limestone, clay and gypsum and goes through a lengthy process before it reaches us. When we build, the cement is then mixed with sand, water, and stone to form concrete.
When mixing concrete, water is the most important additive.
It has to be clean and pure water, otherwise it may affect the strength of the concrete.
And the water:cement ratio is of critical importance to ensure the most perfect mix.
But there is another secret.
Concrete does not gain its strength by drying out.
The secret is to keep it wet for as long as possible!
The simplest way to explain this is that the cement particles have tiny little “arms” that grow and attach to each other. The more of these arms can find each other and get a good grip, the stronger the concrete mix will be. But these arms need water to grow.
(Can you recall those Gremlin movies? One film in the school hall that is forever imprinted in my mind! How on earth they allowed us little ones in, heaven knows. Those cuddly pom-poms that turned into monsters when water hit them, had me running in my dreams for a long time!)
The idea is to keep the concrete wet so that as many as possible of the little arms can grow and fix a strong bond with all the other particles around it. This can then be tested at 28 days. In practice however, concrete can take years to reach its maximum strength.
On building sites all around you, this is the reason that concrete that has been cast is kept wet for weeks on end.
There is method behind the madness.
You might feel as if the water is getting deeper, and it feels as if you are sinking.
But in His wisdom, He knows it makes you easier to work with.
Stronger in the long run.
And from the very beginning, the Spirit has been sifting you until the right parts of you for your part in your story is all that remains.
So that, years later, you can stand back and proclaim: It was good.
“Love is more important than anything else.
It is what ties everything completely together.”
Col 3:14 CEV
Your inspiration for the week: Shelter in
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