INCOMPLETE - Two out of three = nothing. What use is a motor without the vibrating hose to go with it. This is what was received by one customer from C Bury Sales Ltd in Blackburn. The order was placed via an Ebay advertisement on the telephone. The lady working for Chris Bury said the items (all of the package) would be with the customer within 3 or 4 days. Sadly, one item was missing, the 4 meter hose and head, meaning that the motor unit was useless.
Then, it is alleged, that when telephoning to ask what had happened to the four meter hose, (Kelsy) the sales assistant said the customer had signed for three packages. That was not the case, but the customer was now worried. On another call Chris Bury said he'd chase and if necessary send out a replacement, indicating that this was not his fault, but the fault of TNT the carrier.
After more than two week TNT were contacted and confirmed that they'd not delivered three packages, only two being scanned in. That appeared to mean that TNT had not been given a third package of a three package consignment.
Cement has been around for at least 12 million years. When the earth itself was undergoing intense geologic changes natural cement was being created. It was this natural cement that humans first put to use. Eventually, they discovered how to make cement from other materials.
Concrete is a compound material made from sand, gravel and cement. The cement is a mixture of various minerals which when mixed with water, hydrate and rapidly become hard binding the sand and gravel into a solid mass. The oldest known surviving concrete is to be found in the former Yugoslavia and was thought to have been laid in 5,600 BC using red lime as the cement.
The Assyrians and Babylonians used clay as the bonding substance or cement. The Egyptians used lime and gypsum cement. In 1756, British engineer, John Smeaton made the first modern concrete (hydraulic cement) by adding pebbles as a coarse aggregate and mixing powered brick into the cement. In 1824, English inventor, Joseph Aspdin invented Portland Cement, which has remained the dominant cement used in concrete production. Joseph Aspdin created the first true artificial cement by burning ground limestone and clay together. The burning process changed the chemical properties of the materials and Joseph Aspdin created a stronger cement than if using plain crushed limestone could produce.
The first major concrete users were the Egyptians in around 2,500 BC and the Romans from 300 BC The Romans found that by mixing a pink sand-like material which they obtained from Pozzuoli with their normal lime-based concretes they obtained a far stronger material. The pink sand turned out to be fine volcanic ash and they had inadvertently produced the first 'pozzolanic' cement. Pozzolana is any siliceous or siliceous and aluminous material which possesses little or no cementitious value in itself but will, if finely divided and mixed with water, chemically react with calcium hydroxide to form compounds with cementitious properties.
The Romans made many developments in concrete technology including the use of lightweight aggregates as in the roof of the Pantheon, and embedded reinforcement in the form of bronze bars, although the difference in thermal expansion between the two materials produced problems of spalling. It is from the Roman words 'caementum' meaning a rough stone or chipping and 'concretus' meaning grown together or compounded, that we have obtained the names for these two now common materials.
Building a Dam using steel reinforced concrete