Academic reading practice test 6 Amber-Frozen Moments in Time
Amber – Frozen Moments in Time
Amber has a deep fascination both for ordinary people as a gem and for the scientist for whom it provides a glimpse into the past, a window into history. The majority of amber which has been discovered and studied originates in the Cenzoic Era. The earlier Mesozoic which consists of the Cretaceous, Jurassic and Triassic periods has also produced amber but in smaller and scarcer quantities due to its much older age. One of the problems associated with Mesozoic amber is the level of degradation it undergoes. Ancient fossil resin can be badly affected by oxidation, erosion, excessive heat and pressure.
The Death of the Wild Salmon
The last few decades have seen an enormous increase in the number of salmon farms in countries bordering the north Atlantic. This proliferation is most marked in two countries famous for their salmon, Norway and Scotland. Salmon farming in Norway and Scotland has expanded to become a major industry and as the number of farmed salmon has exploded, the population of its wild relatives has crashed. The rivers of these countries that used to have such great summer runs of fish every season that they used to attract thousands of anglers from all over the world are now in perilous decline. Recently Truls Halstensen, a Norwegian fishing writer, wrote that his local river, the Driva, where he used to be able to catch five or more fish of over 20 pounds weight in a morning, is now almost totally fishless
The Can – A Brief History Lesson
The story of the can begins in 1795 when Nicholas Appert, a Parisian, had an idea: why not pack food in bottles like wine? Fifteen years later, after researching and testing his idea, he published his theory: if food is sufficiently heated and sealed in an airtight container, it will not spoil. In 1810 Peter Durand, an Englishman, wanted to surpass Appert’s invention, so he elected to try tin instead of glass. Like glass, tin could be sealed airtight but tin was not breakable and was much easier to handle. Durand himself did no canning, but two other Englishmen, Bryan Donkin and John Hall, used Durand’s patent. After experimenting for more than a year, they set up a commercial canning factory and by 1813 they were sending tins of food to British army and navy authorities for trial.