How it works : Science experiments

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Step 4

Step 5 Conclusion

Step 4. Now take a sheet of black Step 5. Finally, set up your three components like this on a stable So what have we learnt
card and bend it slightly so it surface. Distance between each part is important in the return of from this? If the
curves. This will allow you to optimal results. With a greater distance between pen, needles and card experiment has been a
stand it on its end, where it will your interference pattern should have greater fringe spread (the light success, you’ll have a
remain upright without clamps. waves will diffract more), however if closer together you will get more single light source
This will act as your firing board, intense bands of light and dark. Just experiment to see what works best emanating from the laser
onto which your laser pen will for you. pen that, once passing
shine through the needle slits. though the double needle
Step 6 slits, seems to generate
Interference multiple light bands on the
black card, interspersed
The light with bands of no light at
waves all. If this is the case for you
interfere with then great, as you have just
each other, demonstrated how light
adding particles (photons) act both
together as particles and as waves.
or cancelling The experiment has
each shown that when photons
other out. en masse (projected from
the laser pen) pass through
Radiate the two slits, they radiate
outwards as waves – just
The light like that of water waves –
rays act as either combining or
waves, cancelling each other out
radiating dependent on their electric
outwards field. This explains why on
from the the card we do not just
centre. have two narrow bands of
light directly behind the
two needle slits, but
instead have a wide
spread of light/dark bars
stretching out horizontally.
Take a look at our diagram
on the left for a graphical
representation of how
these processes work.

Double slits Step 6. Once you are happy with the experiment’s layout and that the
laser pen is shining through the needles, kill the lights. If you have been
A single light source passes successful in your preparation you should have something like this
through two slits. marking your card – narrow bands of interchanging light and no light
radiating out in intensity from a central spot. If your lines are too blurry
and the fringes are blending together, try moving the pen closer to the 151
needles. If you just get an intense red dot, ensure your needles are close
enough together and that your pen, needles and card are not too close.

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glossary

Acid Bacteria Chemical reaction

A substance that produces positively charged particles Microscopic single-celled organisms, found almost A process during which one or more substances are
made of oxygen and hydrogen, called hydronium ions, everywhere on Earth. Most bacteria are harmless, but changed into one or more new substances by
when dissolved in water. Vinegar and citrus juices some can cause diseases. rearranging their atoms.
are acids.
Barometer Chlorophyll
Aerial
A device for measuring atmospheric pressure. The green substance in plants that is responsible for
The part of a radio set that sends or receives absorbing the light energy used in photosynthesis.
radio signals. Base
Chromatography
Aerodynamics Bases produce negatively charged particles in water,
called hydroxyl ions. Baking soda and bleach are bases. A process for separating a mixture by passing it through
The study of how gases, especially air, low around a material, such as paper.
solid objects. Battery
Chromosome
Air A device that uses a chemical reaction to make
electricity. A structure found in the nucleus of living cells that
The mixture of gases that surrounds Earth. Air mainly contains genetic information. Chromosomes are made
consists of nitrogen (78%), oxygen (21%), and argon Camera obscura of DNA and proteins.
(0.9%). There are also small amounts of carbon dioxide,
water vapour, and other gases. A darkened box or room with a hole or lens at one side Circuit
that projects images onto a screen on the other side.
Air pressure A complete and closed path around which an electric
Catalyst current can low.
The force exerted by molecules in the air pressing against
something. Sometimes referred to as atmospheric A substance that changes the rate of a chemical Colloid
pressure – the weight of the air molecules in Earth’s reaction without being changed permanently by
atmosphere pressing down on Earth’s surface. the reaction itself. A mixture of large molecules or tiny particles of one
substance spread throughout a second substance.
Air resistance Catalytic converter
Combustion
The friction a solid object experiences as it moves Part of a vehicle engine that changes harmful exhaust
through air. Objects that are streamlined encounter less gases into less harmful gases. Another name for burning – a chemical reaction in
air resistance and move more quickly through air. which a substance combines with oxygen and gives
Celsius out heat energy.
Alkali
A temperature scale named after Swedish scientist Compound
A base that can be dissolved in water. Anders Celsius (1701–1744). On the Celsius scale,
water freezes at 0°C (32°F) and boils at 100°C (212°F). A substance containing atoms of two or more elements.
Amplitude
Centrifuge Compression
The height of a wave, measured from its centre line
to its peak. A machine used for spinning mixtures at high speed 1. Squeezing something together into a smaller space.
to separate the contents according to their mass 2. The part of a sound wave where the air molecules are
Anemometer or density. squeezed together.

A device for measuring the speed of the wind. Centripetal force Condensation

Antibiotic A force directed towards the centre of a curve or A change of state where a gas turns into a liquid, usually
circle that makes a moving object travel in a curved because of a drop in temperature.
A medicine that kills or slows the growth of or circular path.
micro-organisms, especially bacteria. Conduction
Charge
Atom The transfer of heat or electricity through something.
An excess or shortage of electrons. Objects can be
The smallest part of an element that has the positively charged or negatively charged. Conductor
chemical properties of the element. It is made of a
positively charged nucleus surrounded by negatively Chemical A substance that allows heat or electricity to pass
charged electrons. The positive and negative charges through it easily.
are balanced, so an atom is electrically neutral. Any substance that can change when joined or mixed
with another substance. Constellation

A pattern of stars as observed from Earth.

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Convection Electron Friction

The transfer of heat energy in a liquid or a gas caused A negatively charged particle of matter that orbits an A force caused by one surface rubbing against another.
by the tendency of warmer liquid or gas to rise, and atom’s nucleus.
colder liquid or gas to sink. Galvanize
Element
Cotyledon Coat iron or steel with zinc to prevent it from rusting.
A substance that cannot be broken down into a simpler
The food stores that a young plant feeds off until it can substance by chemical reactions. Gamma rays
carry out photosynthesis for itself.
Emulsifier Electromagnetic waves with the shortest wavelength on
Crystal the electromagnetic spectrum.
A substance that stops an emulsion from separating.
A solid with a highly regular arrangement of atoms. Egg yolk is often used as an emulsiier in cookery. Gas

Density Emulsion One of the four states of matter. Gas molecules are
further apart than those in liquids – they are not linked
The amount of mass in a given volume. Minute droplets of one liquid spread throughout a to each other at all, and expand to ill a container.
second liquid with which it normally does not mix.
Diode Milk is an emulsion of fat droplets in a watery luid. Germination

An electronic component that lets an electric current Endothermic The point at which a seed begins to sprout into a plant
pass through it in one direction only. after lying dormant in the soil.
A process or chemical reaction that absorbs energy
DNA in the form of heat. Glucose

Deoxyribonucleic acid. Contains instructions for the Energy A simple sugar that is used as an energy source in many
growth and functioning of an organism. living things.
The ability or capacity to do work. Energy is measured
Drag in joules. It can take many forms, such as kinetic Gravity
(movement) energy and potential (stored) energy.
Resistance to motion through a liquid or gas. Boats An attractive force that all masses have. The greater
moving through water and aircraft moving through air Evaporation the mass, the stronger the gravitational pull. Gravity
are slowed down by drag. The faster something tries to holds moons in orbit around planets, and planets in
move, the more drag it experiences. A change of state where a liquid turns into a gas, orbit around stars.
usually because of an increase in temperature.
Effervescent Haemoglobin
Exothermic
Fizzing or giving off bubbles. The part of the blood that is responsible for transporting
A process or chemical reaction that gives out energy oxygen around the body.
Effort in the form of heat.
Heat
The force needed to move a load. Fahrenheit
A form of energy, caused by the motion of molecules.
Electric current A temperature scale named after German scientist Heat lows from hot substances to cold substances, and
Daniel Fahrenheit (1686–1736). On the Fahrenheit scale, is transferred by conduction, convection, and radiation.
A low of electrons through a conductor. The size of an water freezes at 32°F (0°C) and boils at 212°F (100°C).
electric current is measured in amperes, or amps. The Hemisphere
faster the electrons move, the greater the current. Filament
Half of a sphere.
Electrochemistry A thin piece of wire that heats up when an electric current
passes through it. Electric heaters and incandescent Hydraulic
The branch of chemistry concerned with the effect of bulbs use ilaments to produce heat or light.
electricity on chemical reactions, and the production Moved or operated by a liquid. Hydraulic machinery
of electricity by chemical reactions. Fluorescent is powered by a liquid (usually oil or water) pumped
through pipes at high pressure.
Electrolyte Absorbing light at one wavelength and then giving it out
again at a different wavelength. Incandescent
A solution that conducts electricity, because it
contains ions. Force Glowing because of heat.

Electromagnet A push or a pull that changes the motion of an object. Indicator

A magnet that works only when an electric current Freezing A substance that changes colour when it is mixed with
is lowing through it. an acid or a base.
A change of state that involves a liquid turning into
Electromagnetic spectrum a solid, usually by reducing its temperature. Inert

A group of energy waves arranged in order of Frequency Chemically non-reactive.
increasing wavelength. It includes radio waves,
microwaves, infrared waves, visible light, ultraviolet The number of waves, or cycles, that pass a point in Infrared
waves, X-rays, and gamma rays. a second, measured in cycles per second, or hertz.
Electromagnetic radiation that is outside of the visible
spectrum and is commonly felt as heat.

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Insulator Membrane Nucleus

A substance that does not let heat or an electric current A lexible barrier that controls the low of material in and 1. The central part of an atom.
pass through it easily. out of something, such as a cell. 2. The part of a living cell that contains DNA and
controls the cell’s growth and functioning.
Ion Meteorite
Oxidation
An atom or molecule that has an electric charge A piece of rock or metal from space that passes through
because it has gained or lost electrons. the atmosphere and lands on Earth’s surface. The process where a substance reacts with oxygen
to produce an oxide. Rusting is an oxidation reaction.
Isobar Meteorologist
Oxide
A line on a meteorological chart that connects areas A scientist who studies the weather.
of the same pressure. A chemical compound containing oxygen.
Micro-organism
LED Oxygen
Any microscopic thing that is alive – including bacteria
Light emitting diode. An electronic component that and fungi. One of the gases in air, essential for most of the life
lights up when a small electric current lows through it. on Earth.
Microphone
Lens Pendulum
A device that changes sound waves into an
A piece of transparent plastic or glass that bends light electric current. A weight hanging from a point so that it can swing freely.
rays together or apart as they pass through it.
Microwave Photosynthesis
Lift
Electromagnetic radiation that has a wavelength shorter The process by which green plants make food from
A force that acts upwards. For example, the force that than radio waves but longer than infrared radiation. carbon dioxide and water using the energy of sunlight.
supports the weight of an aircraft when it is lying.
Mineral Phototropism
Liquid
A naturally occurring substance, such as rock, produced A plant’s response to light – plants turn and bend so
One of the four states of matter. A liquid is made of by geological processes. Some minerals are valuable they grow towards light.
molecules that are further away and not as rigidly linked because metals or other useful materials can be
as those in solids. A liquid lows to take up the shape extracted from them. These minerals are called ores. Pitch
of its container.
Mixture The property of a sound that makes it high or low.
Load
Two or more substances that are mixed together but are Plant embryo
A heavy object. not chemically combined.
The part of a seed that grows into a plant. It is made up
Machine Molecule of the plumule, the radicle, and one or two cotyledons.

A device that changes one force into another to make The smallest part of an element or compound, made Plasma
work easier. of two or more atoms linked together.
A gas-like state of matter so hot that its atoms lose
Magnet Monomer their electrons.

A piece of material that attracts some metals, A molecule that forms a polymer when repeated in Plastic
especially iron. a long chain.
A material that is made of polymers and can be
Magnetic field Motor moulded and shaped when soft. Plastics are strong,
supple, and very versatile.
The area around a magnet in which its effects are felt. A machine that changes electrical or chemical energy
into motion. Plumule
Mass
Neutralize The part of a seed that becomes a plant’s shoot.
The amount of matter that something contains.
To make an acid or a base into a neutral solution, i.e., Pneumatic
Matter make it neither acidic nor basic.
Moved or operated by pressurized gas, usually air.
Everything that has mass and ills up space is made Non-Newtonian fluid
of matter. Polymer
A liquid that behaves more like a solid when pressure
Mechanical advantage is applied to it, and so does not obey the usual laws of A simple molecule, that is made up of a monomer
luids that were discovered by English scientist Sir Isaac repeated in long chains.
The increase of force that you get when you use a Newton (1642–1727).
machine to do something. Power
Nucleation
Melting The rate at which work is done or energy is converted
A process that creates gas bubbles in a liquid, or water from one form to another form. Power is measured
A change of state that involves a solid turning into a droplets or ice crystals in air. The bubbles, droplets, or in watts.
liquid, usually by increasing its temperature. crystals form in or around points, holes, or specks
called nucleation sites.

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Pressure Semi-permeable Transpiration

The amount of force that is acting on a given area. Allowing some things to pass through, but not others. The process by which plants move water from the
Pressure is measured in newtons per square metre (also ground by taking it up through their roots, moving it
called Pascals) and pounds per square inch. Siphon through the plant, and then evaporating it from their
leaves and lowers.
Pulley A tube that transfers a liquid upwards from one
container and down to another at a lower level by Ultraviolet
A type of simple machine consisting of a wheel with a atmospheric pressure and gravity.
groove around the rim to take a rope. A pulley changes A form of electromagnetic radiation with a wavelength
the direction of a force. Two or more pulleys used Solid shorter than visible light and longer than X-rays.
together make it easier to lift a load.
One of the four states of matter. Solids are made of Voltage
Quinine molecules that are arranged in a regular pattern. Solid
materials have a deinite shape. They do not low or The electrical pressure that pushes electrons around
A bitter-tasting chemical compound that is used as an take up the shape of their container. a circuit.
ingredient in tonic water. It glows when an ultraviolet
light is shone on it. Solution Volume

Radiation A solid, liquid, or gas that is a mixture of one substance The size of the three-dimensional space occupied
dissolved evenly in another substance. by something or enclosing something.
1. Energy travelling in the form of electromagnetic
waves or particles. Spectroscopy Water vapour
2. The transfer of waves of heat energy from a hotter to
a cooler place. The study of the light that an object gives out. Water in its gas form, usually formed after boiling water
or melting ice.
Radicle Spectrum
Wavelength
The part of a seed that becomes a plant’s root. A band of colours or electromagnetic waves, spread out
in the order of their wavelengths. The distance between the crest of one wave and the
Radio wave crest of the next wave.
State of matter
The longest waves on the electromagnetic spectrum. Weight
They have the lowest frequency and lowest energy. One of the four forms in which matter exists – solid,
liquid, gas, and plasma. The force of gravity acting on a mass. Mass is constant,
Reaction but weight changes with the gravity acting upon it. For
Static electricity example, on the Moon you weigh only one sixth of your
1. A response to something happening. weight on Earth as the Moon’s gravitational pull is
2. A force that is the same in magnitude, but opposite in An electric charge caused by a build-up of electrons on weaker than Earth’s.
direction, to another force. Every force has a reaction. the surface of something.
3. See chemical reaction. Work
Steam
Reflection The amount of energy needed to perform a task.
The gaseous state of water, also known as water
A change in direction of a wave, such as light or sound, vapour. At sea level, water normally boils and changes X-ray
when it bounces off a surface. to steam at 100°C (212°F). Sometimes used to refer to
the cloud of droplets that you see as a mist, for example Electromagnetic radiation with high energy and short
Refraction from a boiling kettle, when water vapour condenses wavelength. X-rays have wavelengths shorter than
back into liquid in the air. The drops you can see are ultraviolet light but longer than gamma rays.
A change in direction of a wave, such as light or sound, water; steam is invisible.
when it travels from one substance into a different Xylem
substance, or through a lens. Streamlined
Pipe-like tissue in plants that transports water from the
Resistance Shaped in a way that offers very little resistance to the roots to the rest of the plant.
low of liquid or gas. A ish with a streamlined body
A measure of how much an electrical component moves through water easily. High-speed cars, trains,
opposes the low of electric current. and aircraft have streamlined bodies.

Resonance Sublimation

The tendency of an object to vibrate more strongly at A change of state where a solid turns directly into a gas,
some frequencies than others. without becoming a liquid irst.

Rotor Surface tension

The rotating part of a machine. A skin-like property of the surface of a liquid, caused
by the molecules on the liquid’s surface being bonded
Salt together more strongly than those underneath.

1. A substance that is formed by a chemical reaction Thrust
between an acid and a base.
2. Another name for sodium chloride. A force that propels a vehicle in one direction, usually by
accelerating gas in the opposite direction by means of a
jet or rocket engine.

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index drag racer 56–57 colloids 29
drench a friend 61 convection currents 74
dry ice 14–15 exhaust 35

in izzy drinks 64

A C E spectroscopy and 83
water vapour 123
acids 36–39 cabbage indicator 37 Edison, Thomas 105 germination 124–125
aerodynamics 52–53 cacti 128 eggs, absorbent 131 Goddard, Robert H 67
agar 136 camera obscura 90–91 eggshells 44–45 gravity 50–51, 148-149
air pressure 58–63, 67, 120 can crusher 58 elasticity 56–57 and roots 124

isobars 121 carbon dioxide 14–15, 25, 39 electric motors 116–117 and siphon 63

air resistance 50, 51 in pumice 29 electricity 97, 115 Guericke, Otto von 58

see also drag carbonic acid 39 currents 102–103, 106–107, 108,

aircraft 52–53 carrots, reviving 130–131 115, 116 H
contrails 64 cars resistance 104–105

alkalis 36 exhaust gases 35 static 98–101 haemoglobin 113

alum 16–17 wheels 56 electrolytes 106–107 heat 76–79

amber 101 catalysts 34–35 electromagnetism 114–117 transfer 74–75

amperes (amps) 103 catalytic converters 35 metal detector 110–111 hovercraft 54–55
ampliier 95 celery 129 radiation 74, 81, 85 Hubble Space Telescope 88
anemometer 121 centre of gravity 50, 51 electromagnets 114–115, 116 hydrangeas 37
antibiotics 137 centrifuge 30, 31 electrons 98, 100, 101, 103, 105, 143 hydraulics 68–69
apple, preserving 33 centripetal force 48–49 electroplating 40–41 hydrogen peroxide 34–35
aqueduct, Roman 44 chemical reactions 32–35 electroscope 100–101 hydronium and hydroxyl ions 36

arches 44 neutralization 38–39 elephant’s toothpaste 34–35

Archimedes 21 chemistry 11 emulsions and emulsiiers 28, 29 I
architecture 44 chlorophyll 85, 142 endothermic reaction 32

arrested descent 49 chromatography 31 energy 32, 57, 73 ice 13, 76–77, 143, 146-147

astronomy 83, 88–89 chromosomes 135 saving 105 can crusher 58

atoms 32, 82, 83, 98, 103 clouds 122–123 see also heat; light; sound dry ice 14–15

in magnetic materials 113 colloids 28–29 exothermic reaction 32, 35 salting 77

aurorae 12 colours 24, 31, 80–83 eyes 90 indicators 36–37
of lowers 128–129 Industrial Revolution 79
B F inks, coloured 31
combustion 32 insulators 103
bacteria 136–137 compass 115, 141 fairground rides 48 iodine 127
baking soda 38, 39 compounds 32 Faraday, Michael 115, 117 ionosphere 109
balloon hovercraft 54–55 compressions 93, 95 iltration 31 ions 36, 40, 107
condensation 122–123

bananas, over-ripe 85 conduction 74 ire 32 iron 32, 40, 113

barometer 120 conductors 100, 103, 105 izzy drinks 64–65, 143 isobars 121

bases 36–39 contrails 64 izzy fountain 24–25

batteries 106–107 convection currents 74 lashlight 102–103 J
beach ball elevator 69 copper plating 40 Fleming, Alexander 137

blood 30, 113 cranes 70–71 loating and sinking 22–23 jelly, luorescent 84
boats crystals 16–17 luorescence 84–85, 105 jet packs 34 w
Ctesibius of Alexandria 68 food preservation 33
how they loat 22 forces 43 L
paddle-powered 57 D fountains 59
steam-powered 78–79 lava fountain 24–25
bomb, baking soda bag 39 lava 24–25

bottles, musical 94–95 density 20–25, 74 frequencies 94–95, 108 lemon batteries 106

breakfast cereal 113 diggers, mechanical 69 friction 54–55, 148-149 lenses 88–89, 90–91

bridges 44 distillation 12 frost 15, 123 lift 53

broad beans 124–125 divers 23 fruit 33, 85, 106, 132, 134–135 light 144-145

bubbles 14–15, 18–19, 24–25 DNA 134–135 colours 80–83

burning 32 domes 44 G luorescence 84–85
butter 28 drag 50, 53, 55 focusing 90–91

see also air resistance gases 12–13 photosynthesis 126–127

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relection 86–87 O fuel 34, 67 tonic water 84, 85
refraction 88–89 space 47, 66, 67 torch 102–103

spectroscopy 82–83 Oersted, Hans Christian 115 two-stage 66–67 traction 56, 57

torch 102–103 oil rotting fruit 33 transpiration 128–129

ultraviolet 84, 85 density 20, 24–25 rubber bands 56–57 trees 130

wavelengths 81, 83 emulsiied 29 rust 32 triangles 44

light bulbs 104–105, 107 Orion Nebula 83 turbines 79

lightning 93, 99, 141 Oscars (Academy Awards) 41 S U
liquids 12–13, 14 osmosis 130–131
oven, solar 75 salt 77, 107
convection currents 74

density 20, 22–25, 74 oxidation 32 science, beneits of 119 ultraviolet light 84, 85

hydraulics 68–69 seeds, germinating 124–125

mixtures 29 P senses 132–133 V
non-Newtonian 26, 27 shapes

siphoning 63vw paper chromatography 31 streamlined 55 vibrations 94–95

surface tension 18–19 paper planes 52–53 strong 44–45 vinegar 32, 39, 40, 131

see also water parachutes 50 silver volcanoes 38–39

pendulums 49 as catalyst 34 Volta, Alessandro 107

M penicillin 137 cleaning 41 volume 21
periscope 86–87 silver sulphide 40, 41

maglev trains 114 photography 91 siphon 63 W
magnetism 97, 112–113, 115, 141 photosynthesis 126–127 slime 26–27

see also electromagnetism phototropism 127 smell 132 water

mass 20, 21 plants 85, 124–127 snake charming 98 bending 101

matter 11 osmosis 130–131 soda shoot 64–65 condensation 122–123

states of 12–13 transpiration 128–129 solids 12, 13 density 20, 22–25, 74

mechanical advantage 71 plasma 12 sorbet 77 distillation 12

membranes 130, 131 plastic 26, 27 sound 92–95, 108, 142 as electrolyte 107

metal detectors 110–111 plating 40–41 spectroscopy 82–83 freezing 13

meteorites 112 pneumatic tubes 63 spinning 48–49 plants and 128–131

micro-organisms 33 polymers 26–27 centrifuge 30, 31 and sound 92

microphone 92–93 pond skaters 19 sports 133 steam power 78–79

Millennium Seed Bank 125 pulleys 70–71 squares 45 surface tension 18–19

mine detectors 110 pumice 29 starch 26, 27, 127 see also liquids

mirrors 86–87 stars 83, 88 water vapour 123

missile launcher 62–63 Q static electricity 98–101 Watt, James 79
mixtures 28–29 steam power 78–79 wavelengths

separating 30–31 quicksand 27 Streptococcus pyrogens 137 light 81, 83

molecules 32 quinine 84, 85 sublimation 14–15 sound 95, 108

and friction 54 submarines 23, 87 wax lamps 25

heating and cooling 13, 14, 74 R suction, unsuccessful 58 weather 120–123
in liquids 14, 19, 20 sugar 16 weight lifting

and osmosis 130 radiation Sun hydraulics 69

stretching 57 electromagnetic 74, 81, 85 colours of visible light 80 pulleys 70–71

Moon 51 solar 74, 75 photosynthesis 126–127 whales 92

motion, laws of 46–47, 79, 148 radio, homemade 108–109 radiation 74, 75 wind 120

motors, electric 116–117 radio signals 108–109, 111 ultraviolet rays 85 speed 121

musical instruments 68, 94–95 rainbow colours 80–83 sunlowers 126, 129

surface tension 18–19
swinging 49
rainforest 129
xylem 128–129
Xreactions, human 132–133
N relection 86–87

neutralization 38–39 refraction 88–89 T Y
Newcomen, Thomas 79 refrigeration 33
Newton, Isaac 26, 46, 79 resistance, electrical 104–105 taste 132

Niepce, Joseph 91 resonance frequency 94–95 telescope 88–89 yeast 34–35

nucleation 64–65 rockets thrust 53

bottle 46–47 thunderstorms 93, 99

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37bl; NASA - Hubble Heritage Team - di / 40-41; Donald Erickson 51br, 51crb; Darren
Science Faction 88bl; Charles O’Rear 68br; Hubley 39tl; Mikhail Kokhanchikov 89t; Evgeny All other images © Dorling Kindersley
Christine Osborne 69bc; Jim Reed / Jim Reed Kuklev 96-97, 98-99, 100-101, 102-103, For further details see: www.dkimages.com

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