This is an extract from an Academic Reading passage on the subject of dung beetles. The text preceding this extract gave some background facts about dung beetles, and went on to describe a decision to introduce nonnative
varieties to Australia.]
Introducing dung 1 beetles into a pasture is a simple process: approximately 1,500 beetles
are released, a handful at a time, into fresh cow pats 2 in the cow pasture. The beetles
immediately disappear beneath the pats digging and tunnelling and, if they successfully
adapt to their new environment, soon become a permanent, self-sustaining part of the
local ecology. In time they multiply and within three or four years the benefits to the
pasture are obvious.
Dung beetles work from the inside of the pat so they are sheltered from predators such
as birds and foxes. Most species burrow into the soil and bury dung in tunnels directly
underneath the pats, which are hollowed out from within. Some large species originating
from France excavate tunnels to a depth of approximately 30 cm below the dung pat.
These beetles make sausage-shaped brood chambers along the tunnels. The shallowest
tunnels belong to a much smaller Spanish species that buries dung in chambers that hang
like fruit from the branches of a pear tree. South African beetles dig narrow tunnels of
approximately 20 cm below the surface of the pat. Some surface-dwelling beetles,
including a South African species, cut perfectly-shaped balls from the pat, which are
rolled away and attached to the bases of plants.
For maximum dung burial in spring, summer and autumn, farmers require a variety of
species with overlapping periods of activity. In the cooler environments of the state of
Victoria, the large French species (2.5 cms long), is matched with smaller (half this size),
temperate-climate Spanish species. The former are slow to recover from the winter cold
and produce only one or two generations of offspring from late spring until autumn. The
latter, which multiply rapidly in early spring, produce two to five generations annually.
The South African ball-rolling species, being a sub-tropical beetle, prefers the climate of
northern and coastal New South Wales where it commonly works with the South African
tunneling species. In warmer climates, many species are active for longer periods of the
year.
Glossary
1. dung: the droppings or excreta of animals
2. cow pats: droppings of cows
[Note: This is an extract from an Academic Reading passage on the development of rockets. The text preceding this extract explored the slow development of the rocket and explained the principle of propulsion.]
| The invention of rockets is linked inextricably with the invention of 'black powder'. Most historians of technology credit the Chinese with its discovery. They base their belief on studies of Chinese writings or on the notebooks of early Europeans who settled in or made long visits to China to study its history and civilisation. It is probable that, some time in the tenth century, black powder was first compounded from its basic ingredients of saltpetre, charcoal and sulphur. But this does not mean that it was immediately used to propel rockets. By the thirteenth century, powder-propelled fire arrows had become rather common. The Chinese relied on this type of technological development to produce incendiary projectiles of many sorts, explosive grenades and possibly cannons to repel their enemies. One such weapon was the 'basket of fire' or, as directly translated from Chinese, the 'arrows like flying leopards'. The 0.7 metre-long arrows, each with a long tube of gunpowder attached near the point of each arrow, could be fired from a long, octagonal-shaped basket at the same time and had a range of 400 paces. Another weapon was the 'arrow as a flying sabre', which could be fired from crossbows. The rocket, placed in a similar position to other rocket-propelled arrows, was designed to increase the range. A small iron weight was attached to the 1.5m bamboo shaft, just below the feathers, to increase the arrow's stability by moving the centre of gravity to a position below the rocket. At a similar time, the Arabs had developed the 'egg which moves and burns'. This 'egg' was apparently full of gunpowder and stabilised by a 1.5m tail. It was fired using two rockets attached to either side of this tail. |
| It was not until the eighteenth century that Europe became seriously interested in the possibilities of using the rocket itself as a weapon of war and not just to propel other weapons. Prior to this, rockets were used only in pyrotechnic displays. The incentive for the more aggressive use of rockets came not from within the European continent but from far-away India, whose leaders had built up a corps of rocketeers and used rockets successfully against the British in the late eighteenth century. The Indian rockets used against the British were described by a British Captain serving in India as ‘an iron envelope about 200 millimetres long and 40 millimetres in diameter with sharp points at the top and a 3m-long bamboo guiding stick’. In the early nineteenth century the British began to experiment with incendiary barrage rockets. The British rocket differed from the Indian version in that it was completely encased in a stout, iron cylinder, terminating in a conical head, measuring one metre in diameter and having a stick almost five metres long and constructed in such a way that it could be firmly attached to the body of the rocket. The Americans developed a rocket, complete with its own launcher, to use against the Mexicans in the mid-nineteenth century. A long cylindrical tube was propped up by two sticks and fastened to the top of the launcher, thereby allowing the rockets to be inserted and lit from the other end. However, the results were sometimes not that impressive as the behaviour of the rockets in flight was less than predictable. |
Questions 7 – 10
Look at the following items (Questions 7-10) and the list of groups below.
Match each item with the group which first invented or used them.
Write the correct letter A-E in boxes 7-10 on your answer sheet.
NB You may use any letter more than once.
7 black powder
8 rocket-propelled arrows for fighting
9 rockets as war weapons
10 the rocket launcher
| First invented or used by A the Chinese B the Indians C the British D the Arabs E the Americans |
Read the articles and send your notes to mgruiz@cantv.net (Make a summary of them)
