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The Rocket’s Red Glare
In the 17th century, Sir Isaac Newton published his Third Law: For every action there is an equal and opposite reaction. If you have ever rowed a boat across a quiet lake, you experienced Newton’s law in action. The action of pushing the oars in one direction propelled the boat in the opposite direction. This simple rule of nature is the basis for the rockets that catapult both bombs and people into the air.
The first mention of rockets appeared in various Chinese writings of the 13th century. Several writers report rockets being used to drive off Mongol invaders. Why rockets were invented in China is anyone’s guess. Some historians surmise that the high levels of sulfur and potassium nitrate in the soil may have been accidentally kicked into a campfire, resulting in an explosion. The transition from explosion to rocketry required an additional step. When this explosion is created in a hollow tube that is capped on one end, the force of the explosion is vented through a single opening. This “action” in one direction, moves the tube in an “equal and opposite” direction. The force of the discharge can be increased or decreased by widening or narrowing the opening. This principle can be demonstrated with a garden hose. The smaller the opening, the greater the force of the escaping water.
As with the 13th century Chinese, the first application of this technology in Europe was in weaponry. The ability to send balls of fire at a distant enemy offered a clear advantage in battle. The problem was accuracy. On land, the cannon provided greater leverage for an army because its aim was more precise and its performance more reliable. Moreover, the equipment required for launching rockets proved too cumbersome to move and set up under fire or in bad weather. However, it was at sea that the rocket proved itself to be a practical and effective weapon. The huge canvas sails and tarred hull of an enemy ship offered a perfect target. A single rocket could engulf a ship in flames in a matter of minutes.
As the accuracy of rockets increased, they began to play a part in ground warfare. The V-1 and V-2 rockets developed by the Germans in World War II terrified London. Today’s intercontinental missiles with their atomic warheads are some of the most feared weapons in history.
More recently, people have replaced warheads, and the rocket has become the preferred method of space travel.
catapult
If someone or something catapults or is catapulted through the air, they are thrown very suddenly, quickly, and violently through it.
shoot, pitch, plunge, toss
A catapult is a device for shooting small stones. It is made of a Y-shaped stick with a piece of elastic tied between the two top parts.
surmise
If you surmise that something is true, you guess it from the available evidence, although you do not know for certain.
guess, suppose, imagine, presume
If you say that a particular conclusion is surmise, you mean that it is a guess based on the available evidence and you do not know for certain that it is true.
transition
Transition is the process in which something changes from one state to another.
change, passing, development, shift
To transition from one state or activity to another means to move gradually from one to the other.
vent
A vent is a hole in something through which air can come in and smoke, gas, or smells can go out.
outlet, opening, hole, split
If you vent your feelings, you express them forcefully.
discharge
When there is a discharge of a substance, the substance comes out from inside somewhere.
emission, flow, ooze, secretion
If someone discharges a gun, they fire it.
application
The application of a rule or piece of knowledge is the use of it in a particular situation.
relevance, use, value, practice
An application for something such as a job or membership of an organization is a formal written request for it.
leverage
leverage is the ability to influence situations or people so that you can control what happens.
influence, authority, pull
Leverage is the force that is applied to an object when something such as a lever is used.
cumbersome
Something that is cumbersome is large and heavy and therefore difficult to carry, wear, or handle.
awkward, heavy, hefty, clumsy
A cumbersome system or process is very complicated and inefficient.
practical
Practical ideas and methods are likely to be effective or successful in a real situation.
feasible, possible, sound, viable
You describe people as practical when they make sensible decisions and deal effectively with problems.
engulf
If one thing engulfs another, it completely covers or hides it, often in a sudden and unexpected way.
immerse, bury, flood (out), plunge
If a feeling or emotion engulfs you, you are strongly affected by it.
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