Geotestlab

The Emerald Ring of Polycrates

According to Herodotus, Amasis thought Polycrates was too successful, and advised him to throw away whatever he valued most in order to escape a reversal of fortune. Polycrates followed the advice and threw a jewel-encrusted ring into the sea; however, a few days later, a fisherman caught a large fish that he wished to share with the tyrant. While Polycrates' cooks were preparing the fish for eating, they discovered the ring inside of it. Polycrates told Amasis of his good fortune, and Amasis immediately broke off their alliance, believing that such a lucky man would eventually come to a disastrous end.[46] Within Herodotus' work, this story serves to advance general themes about the mutability of fortune and how to judge success. Most subsequent references to Polycrates in literature and other media have focused on this story.

Herodotus, Father of History (circa 490 to 420 BC). tells the story of King Polycrates of Samos. The king's luck was legendary, but Amasis, an Egyptian colleague, warned him in a letter, "I am pleased to hear, dear friend, that you are doing well; but your abundance of luck gives me pause for thought, as I fear the jealousy of the gods. So take my advice and protect yourself from luck. Reflect on what you love the most, and whose loss would cause you the greatest pain, and throw it away, so that it will never appear again."

When Polycrates had read the letter and had seen that Amasis' advice was good, he considered which of his royal treasures he cherished most. He discovered that it was the emerald set in the gold ring he wore on his finger and used as a seal. It was the work of Theodoros, son of the Samian Telekles. Polycrates decided to dispose of the ring. He summoned a ship with fifty rowers, boarded and ordered the ship out to sea. When he was far from the island, he took off the ring and with all eyes watching. threw it into the sea. He then returned home and was distraught.

Some days later a fisherman honored him with the gift of a large catch:

The fish was opened by the cook,

Who suddenly, with wondering look,

Runs up, and utters these glad sounds. "Within the fish's maw, behold.

MAKE YOUR CONCRETE MORE DURABLE

Fresh concrete has an inhurent tendency to crack and preventive measures at hthe time of placing and curing remain the best means of minimicing cracking

When concrete is placed under high ambient temperatures / low humidity / windy conditions, cracks appear during the setting/hardening period due to evaporation of water from the concrete surface.

Cracks appear in winter also under windy conditions. Further delay in curing would widen and deepen such cracks thereby causing leakages through slabs.

These cracks are known as PLASTIC SHRINKAGE cracks and are commonly observed in concrete footings and slabs. These cracks are classified as non-structural and do not affect structural stability; however, the cracks have to be sealed to achieve the intended serviceability of the structure,

PREVENTIVE MEASURES TO REDUCE AND CONTROL PLASTIC SHRINKAGE
Concrete surface,PREVENTIVE MEASURES TO REDUCE AND CONTROL PLASTIC SHRINKAGE

CRACKING IN CONCRETE

AFTER PLACING THE CONCRETE DO NOT ALLOW CONCRETE TO DRY. START CURING AS SOON AS POSSIBLE. > Moisten the formwork and reinforcement before placing the concrete to prevent moisture loss from concrete.

Arrange adequate manpower to place, compact, finish and cure the concrete without any delays.

▸ Protect concrete during any appreciable delay between placing and finishing Float properly after placing the concrete.

Cover with plastic sheet immediately after finishing, or, Start sprinkling / misting concrete surfaces (care must be taken not to use high pressure hose pipe to sprinkle. they may damage the surface/ wash away cement particles). The plastic sheet needs to be held down properly, if this option is chosen.
Pouring concrete

After the concrete is sufficiently stiffened, place wet hessian on the concrete surface and cover it with plastic sheet to keep the hessian wet for longer time. Make arrangements to keep the hessian wet all the time for the entire specified curing period.

Alternatively, pond water and cure continuously for the specified period, or for at least 7 days. > Ensure appropriate and adequate curing under all circumstances.

REFERENCES

1. Non-Structural Cracks in Concrete, Technical Report No. 22, Concrete Society, U.K., Third Ed.. 1992.

2. Causes, Evaluation & Repair of Cracks in Concrete Structures, ACI 224.1R, American Concres Institute.