had a spinning wheel, spinning work was readily available to
wives. In the 1670s, a female weaver or spinner was paid 2-4d. per
day. A domestic servant, who was usually female, was paid 40-80s.
a year. Men in the trades objected to competition from lower-paid
women. Aristocratic ladies actively managed their family's
household and estates. The only work available to a high middle-
class woman who was waiting to get married was to be a governess
in another household or a lady-in-waiting to a gentlewoman.
Children often worked; this was recommended so that they were
under the direct supervision of their parents rather than getting
into mischief in the village. The mother typically mingled
severity with gentleness, but the father did not dare to err on
the side of leniency. Discipline was by whipping. Children were
treated as little adults. The lack of a conception of childhood
innocence even extended to the practice of adults to tell bawdy
jokes in their presence or play with their children's genitals.
About 1660, the Royal Society of London for the Promotion of
Natural Knowledge was founded by Charles II, who became its
patron. It was formed from discussion groups of the new
experimental philosophy. It included the Baconians formerly at
Oxford and Cambridge, who were ejected at the Restoration, and a
group of Gresham professors of geometry and astronomy. The Royal
Society met at Gresham College. Its goal was to compare ideas in
mathematics and science and identify specific aims of science. It
published scientific reports to make its findings generally known.
This was a great improvement over the private correspondence among
scientists, which was limited by the use of various languages.
Charles himself had his own laboratory and dabbled in chemistry
and anatomy. Similar societies were formed in many places in the
world. Theologicians warned that scientific research was dangerous.
But it's advances improved agriculture, manufactures, medicine,
surgery, navigation, naval architecture, gunnery, and engineering.
Issac Newton was a genius, who in his childhood designed and built
model windmills, water wheels, water clocks, sundials, and kites.
He came from a family which had risen from the yeomen ranks to the
gentry. For a few years after graduating from Cambridge University
in 1665, he secluded himself in the countryside to study. Here,
using the work of John Wallis, he formulated the binomial theorem
that expands (A+B) raised to the nth exponent power, where n is an
integer. He also worked with numbers that had exponents that were
fractions, unending decimals, or negative numbers. Certain
patterns of numbers, such as the sum of doubling each number in a
series as in: 1+2+4+8+...never terminates; the series is infinite.
He then developed the notion of a number being the limit of the
summation of an infinite converging series of a pattern of numbers,
such as the limit of 1+(1/2)+(1/4)+(1/8)...= 2. By considering the
state of motion of a mass-point in an infinitely short time under
the influence of an external force, he developed rules for finding
areas under algebraic curves [integration], such as the hyperbola,
and finding tangents to algebraic curves [differentiation], which
he recognized as inverse processes. That is, differentiating the
integral of a function results in a return to that function.
Newton discovered that colors arose from the separation, rather
than a modification, of white light, that is natural sunlight. He
did this using a prism to dissect the white light into its
spectrum of constituent colors and then using a prism and lens to
recombine the colors to reconstitute white light. The spectrum was
the same as that of a rainbow. He determined the angle of
refraction of each color by beaming white light through a prism,
and then through a hole in a board which isolated one color, to
another prism. When he discovered that all colors reflect from a
mirror at the same angle, he invented and built the reflecting
telescope, which used a parabolic concave mirror and a flat mirror
instead of a convex lens, thereby eliminating the distortions and
rainbow coloring around the edges that resulted from the
refraction of different colors at different angles. He deemed a
ray of light to consist of a rapidly moving stream of atomic
particles, rather than Robert Hooke's pulses or Christian Huygens'
waves, because shadows showed a sharp boundary between the light
and the absence of light. He reasoned that if light was made up of
pulses or waves, it could spread around obstacles or corners as
sound seemed to do. He approximated the speed of sound by timing
echoes in corridors of various lengths.
Newton was methodical and combined the inductive and deductive
methods of inquiry, first making observations, and then
generalizing them into a theory, and finally deducing consequences
from the theory which could be tested by observation. He carried
mathematization of data from experiments as far as possible.
Newton theorized that the same gravity force that pulled an apple
down from a tree extended out to the moon to hold it in its orbit
around the earth. He saw a connection between these movements by
imagining a cannon on a mountain shooting a series of cannonballs
parallel to the earth's surface. The first shot has only a tiny
charge of explosive, and the cannonball barely makes it out of the
muzzle before falling to the ground. The second shot is propelled
by a larger charge, and follows a parabolic arc as it falls. The
next shots, fired with increasingly more propellant, eventually
disappear over the horizon as they fall. Lastly, with enough
gunpowder, a speeding cannonball would completely circle the earth
without hitting it. By extrapolating from these ever faster
projectiles, he opined that the moon was held in its orbit by the
same earth force that operated on the projectiles. He correlated
the moon's orbit with the measured acceleration of gravity on the
surface of the earth. He put various substances with different
masses and weights into the shell of a pendulum and observed that
the pendulum had the same period [time for one oscillation] and
fell at the same rate as free-falling objects. Then he formulated
the idea that the ultimate agent of nature was a force acting
between bodies rather than a moving body itself. Gravity did not
act in proportion to the surfaces of bodies, but in proportion to
quantity of matter. Gravity penetrated to the very center of all
bodies without diminution by the body. Gravity's force extended to
immense distances and decreased in exact proportion to the square
of the distance.
Newton opined that an object moves because of external forces on
it rather than by forces internal to the object. He connected the
concepts of force and acceleration with a new concept, that of
mass. Mass is a quantity intrinsic to an object that determines
how it responds to forces, such as the force of gravity. The
greater the mass of a body, the stronger the force of gravity on
it, and the more difficult it is to get it moving. He found that
the acceleration of a body by a force is inversely proportional to
its mass, and formulated the equation that force equals mass
multiplied by acceleration. So if a force acts on a planet, it
produces a change in velocity that is proportional to the force
and in the same direction as the force. His law of inertia is that
any body, persists in its state of rest or of uniform motion in a
straight line, unless affected by an outside force. His next law
is that when a body A exerts a force on a body B, then B also
exerts a force on A which is equal in amount but opposite in
direction. This means that forces that operate between different
parts of a planet produce no net force upon the whole planet, so
that the mass of a planet can be treated as if it is concentrated
at a point. These are his three laws of motion.
His law of gravitation explains how the whole universe is held
together. This law holds that every object in the universe
attracts every other object with a single gravitational force that
is directly proportional to the product of their masses and
inversely proportional to the square of the distance between their
centers. Newton had first accepted the Cartesian system of
celestial vortices of aether that swirled the planets and comets
around their orbits. He determined that Kepler's law that areas
were swept out in equal times implied that gravity acts in the
direction of a line between the planet and the sun. The gross
features of the universe and Kepler's observations led to his
recognition that the attraction between two bodies decreases
inversely in proportion to the square of the distance between
them. Only one kind of force would satisfy Kepler's requirement
that the sun was a focus of an ellipse and still be consistent
with Kepler's law that the square of a planet's period was
proportional to the cube of its mean distance from the sun; that
was the inverse square law. Then he came to accept Robert Hooke's
hypothesis that planets are kept in their orbits by the
combination of an attractive power of the sun and of motion in a
straight line that was tangential to their orbits. From
astronomical data, he calculated this centripetal acceleration of
each planet towards the sun to be proportional to the inverse
square of its distance from the sun. He also calculated the
"centrifugal" accelerations in a straight line. His experiments
showed that the centripetal force in a circular orbit was equal to
the mass of the body multiplied by the square of its velocity, all
divided by the radius of the circular path. He used calculus and
differential equations to determine centripetal forces of
elliptical orbits, where the distance from the sun, the velocity,
and the acceleration were variables.
Newton showed that his single gravitational force could account
for the way free-falling objects descend to the ground, the
parabolic trajectory of projectiles, the path of the moon in its
orbit around the earth, the course of the tides every twelve
hours, the lower densities of the earth's atmosphere at greater
heights, the paths of Jupiter's moons, the paths of comets, and
the elliptical paths of the planets in their orbits around the
sun. This determination discredited the previous belief that
invisible angels moved the planets. Newton proved from his law of
gravitation and his three laws of motion the truth of Kepler's
laws of elliptical planetary motion. Newton demonstrated from
data collected from the comet of 1680 that comets moved according
to his law of gravitation. He showed that the path of a body
traveling within the gravitational force of the sun is a circle,
an ellipse, a parabola, or a hyperbola. He used the concept of a
common center of gravity as a reference point for other motions.
The fact that the center of gravity of the solar system was within
the body of the sun verified that the sun was indeed at the center
of the solar system.
Newton deduced that the tides were created by the rotation of the
earth with bulges of water on the earth's surfaces that were
closest and farthest from the moon. The moon "pulled" the water
nearest to it with a greater force than average. It "pulled" the
water farthest from it with a force weaker than average. These
two moving bulges created two tides a day.
Newton's "Principia Mathematica Philosophiae Naturalis", was
published in 1687. The established church denounced it as being
against the scripture of the Bible. Newton did not agree with the
established church on many points, such as the trinity, and was
considered a heretic. He had his own interpretations of the Bible
and doubted the divinity of Jesus. But it was accepted for
dissenters like Newton to qualify for full civil rights by
maintaining an outward conformity and taking the sacrament in the
established church once a year. Newton was given a royal
dispensation from taking holy orders as prescribed by the rules
for tenure of fellows of his college at Cambridge University. He
did believe in a God who created the universe and who had a
ubiquitous presence in all space. When Catholic King James II
tried to have a Catholic monk admitted to the degree of a Master
of Arts at Cambridge University without taking the oath of
adherence to the established Protestant church, so that he could
participate in the business of the university, Newton was active
in the opposition that defeated this attempt. As a result, he was
elected to Parliament by Cambridge.
When Olaus Roemer, a Danish astronomer, was applying Newton's laws
to the paths of the moons of Jupiter to make a table of eclipses
of Jupiter's moons for use in determining one's longitude, he
noticed that the eclipses were five hundred seconds ahead of
average time at that time of year when the earth and Jupiter were
on the same side of the sun, and five hundred seconds behind
average time six months later, when Jupiter was on the other side
of the sun. He reasoned that this difference was due to the light
from Jupiter's moons taking more time to reach the earth when
Jupiter was farther from the earth, i.e. on the other side of the
sun. He concluded that light does not travel instantaneously, but
at a certain speed. From the fact that it took 1000 seconds for
light to travel the diameter of the earth's orbit, he calculated
its speed in 1676.
In 1668, Christian Huygens formulated the law of conservation of
momentum [mass multiplied by velocity], which held that when
objects collide, they may each change direction, but the sum of
all their momenta will remain the same. Huygens also recognized
the conservation of what was later called "kinetic energy", which
is associated with movement. He developed laws of centrifugal force
for uniform motion in a circle. He derived the formula for
computing the oscillations of a simple pendulum. In 1690, he
posited the theory that light consists of a series of waves. It
states that all points of a wave front of light in a vacuum may be
regarded as new sources of wavelets that expand in every
at a rate depending on their velocities. He thought this a better
explanation of bending and interference of light than Newton's
particle theory.
In 1661, Robert Boyle, called the father of modern chemistry,
defined an element as a substance that cannot be further
decomposed. He distinguished an element from both a mixture, which
is easily separable, and a compound, which is not easily
separable. He used an air pump he developed and a glass jar to
create a confined vacuum space for experiments to find the
properties of heat, light, and sound. He noted that burning
objects such as candles and coal, when placed in the receiver of
his air pump, went out after a time although air was still
present. He opined that animals were dependent upon a fresh supply
of air to live. He studied the relationship between the volume,
density, and pressure of air and gases. He proved by experiment
that the volume of a gas at a constant temperature varies in
inverse proportion to the pressure applied to the gas. Since gas
is compressible, he opined that gases must be composed of discrete
particles separated by void, and also that basic physical
properties were due to motions of particles, or atoms, which was
an ancient Greek conjecture. This cast doubt on the long-held
belief that everything was composed from four basic elements: air,
water, fire, and earth. Boyle's laboratory at Oxford was
denounced by the Oxford clergy as destroying religion. In 1679,
the steam pressure cooker was invented by Denis Papin from France.
He invented the atmospheric engine in 1690.
Robert Hooke helped Boyle build his air pump. Hooke was thirteen
when his father, a minister, died. Hooke was a genius with innate
mechanical skill and was an able mathematician. He applied a
spiral spring to regulate the balance of watches. A lord financed
him as a Gresham lecturer of geometry for 50 pounds a year. In
1666, he used a pendulum to measure the force of gravity and
showed that the center of gravity of the earth and moon is a point
describing an ellipse around the sun. In 1667, he explained the
twinkling of the stars by irregular atmospheric refractions. He
formulated the theory that light is composed of pulses. Hooke's
Law states that the amount an elastic body such as a spring
stretches out of shape is in direct proportion to the force
acting on it: its tension. He invented the odometer, a wheel to
measure distances. He constructed an arithmetical machine. He
invented the universal joint, which can move in many angles. His
book of drawings of microscopic animals is a classic. He
proposed that fossils can be used as a source of information about
the earth's history. Hooke became rich from his inventions, but
this was not known until his death, when thousands of pounds were
found in his iron chest.
In 1668, Wallis postulated the correct theory of impacts of
inelastic bodies, based on the principle of conservation of
momentum. In 1685, he introduced the first graphical
representation of complex numbers.
Royal astronomer and genius Edmond Halley, the son of a soap
maker, studied tides, magnetism, and the paths of comets and
stars. He went on voyages to study the heavens from different
positions, thereby laying the foundations of physical geography.
He showed that the stars change in position in relation to each
other. With Newton's help, he calculated the orbit of a comet he
saw in 1682 to be elliptical rather than parabolic and then proved
it was the same comet that had appeared in 1531 and 1607,
indicating it's regularity; it was then named "Halley's comet".
However, the Church of England still embraced the idea that comets
and eclipses were evidence of God's wrath. Greenwich Observatory
was built in 1675. Halley used a barometer to measure the density
of the atmosphere and related its readings to elevations into the
atmosphere and to weather. He determined that the cause of the
tropical trade winds was the sun warming the tropical air at the
equator, causing it to rise and move north as it was replaced by
cooler air from the north. This body of air was deflected by the
rotation of the earth. He illustrated the tropical winds with the
first meteorological map. He made a descent in a diving bell,
which was used to try to reach wrecked treasure ships. He studied
fossils and perceived them as remnants of living beings that had
died long ago, and imagined a succession of living things. Halley
surveyed the tides and coasts of the British Channel for the king
in 1701.
In 1675, apothecary Nicolas Lemery divided substances into
mineral, vegetable, and animal. He wrote a dictionary of
pharmaceuticals.
John Ray and Francis Willoughby were friends who traveled together
to study plants and animals respectively. John Ray started the
science of zoology with his edition of Francis Willoughby's
"Ornithology" on birds and his own "History of Fishes". He also
attempted the first scientific classification of animals in his
"Synopsis of Quadrupeds". Ray compared anatomies and experimented
on movements of plants and the ascent of sap. He knew that fossils
were remnants of old animals. Ray first suggested the concept of
species in classification of animals and plants. He opined that
the goodness and wisdom of God was shown not only by the
usefulness of animals to man's uses as taught by the church, but
also by the adaptation of animals to their own lives and
surroundings. The vast array and dispersal of animals found by
world explorers all over the world cast doubt on the biblical
story of Noah putting two of every kind of animal on an ark. The
science of botany began with Ray's "History of Plants" and the
researches of Robert Morrison, who was Charles' physician and
keeper of his gardens.
Nicholaus Steno, a Danish physician, diagrammed six levels of
stratification on the earth's surface and demonstrated in 1669
that layers of strata of rock are always deposited with the
oldest layers on the bottom and the youngest layers on the top.
This began the science of geology. He argued that shifts in the
earth's strata caused the formation of mountains. He identified
fossils as ancient creatures. The idea that fossils were remnants
of dead animals existing before man conflicted with the religious
idea that Adam's fall began sin and caused death. The idea from
fossils that existing species of animals were modifications of
predecessor animals conflicted with the religious belief that
Noah's ark had preserved all the varieties of animals. John Aubrey
described Stonehenge, thus founding prehistoric archaeology. He
thought it to be a Druid temple.
The telescope and compound microscope, which has an objective lens
and an eyepiece lens for producing a wide range of magnifications,
were further developed. The cellular basis of life was discovered
and described by Robert Hooke. Nehemia Grew, the son of a grammar
school master who became a physician, observed and drew plant
anatomy, including leaves, flowers, fruits, seeds, ovules, pollen
grains, and stamens. He was the first to observe the existence of
plant sexuality. Italian Marcello Malpighi, a physician, used the
new compound microscope to study human skin, spleen, kidneys, and
liver and also compared the livers of several types of animals. He
discovered capillaries linking the arterial and venous circulation
in the lungs. Dutchman Anton van Leeuwenhock, a cloth manufacturer
who made microscopes to inspect the quality of cloth, turned them
to use in understanding the life cycles of mites, lice, and fleas.
He correctly described human blood cells. When he found what he
described as tiny animals (bacteria, protozoa, and rotifers), he
sent clear descriptions of them to the Royal Society in London as
proof against the theory of spontaneous generation, which held
that lower forms of life could arise from nonliving matter. This
started the science of bacteriology. With the discovery of the egg
in the female reproductive system, the status of women was lifted.
Physician Thomas Willis, son of a farmer, dissected brains of men
and animals to study the anatomical relations of nerves and
arteries. Excess urine had been associated with a wasting disease.
Willis identified diabetes mellitus with excess of urine that was
sweet. Physician Thomas Sydenham, son of a gentleman, observed
epidemic diseases of London over successive years, thus founding
epidemiology. He also furthered clinical medicine by emphasizing
detailed observations of patients and maintaining accurate
records. He wrote a treatise on gout and identified scarlet fever.
He introduced a cooling method of treating smallpox. But he still
relied on the big three treatments: bloodletting, purging, and
sweating. Bloodletting was to draw off bad blood so that it could
be replaced by a better fluid. Another treatment used was cupping,
whereby a vacuum was created by heated glass cups to draw blood to
the surface of the skin. John Locke performed one of the first
successful operations draining a kind of abscess of a man's liver.
It was common for people who felt ill to take a laxative and rest
at home.
In 1690, physicians opened the first dispensaries, which gave
treatment and medicine together, to take business away from their
rivals: the apothecaries. London's apothecaries were released in
1694 from jury service and serving as constable, scavenger, or
other parish or ward office because it was necessary that they be
available to attend the sick at all times. Peruvian bark which had
quinine as its alkaloid had been introduced as a proven cure for
the ague, a fever with chills usually due to malaria, in 1653. The
English ceased to believe in holy wells, but went to spas such as
Bath for treatment for disease.
There was more bathing because private homes in towns now had
indoor baths. The public baths came into disuse.
For childbirth, only rich women were attended by physicians. Most
physicians used talismen such as the eagle stone at deliveries.
Caesarian section almost always led to the death of the mother.
Midwives were licensed by the church and could baptize babies.
Jane Sharp wrote "The Midwives Book" with anatomical
illustrations.
Women over thirty had fewer children and the last child born was
at an earlier age than before. This was in part due to birth
control such as coitus-interruptus, long breast-feeding of a
current child and/or the taboo against sex if the wife was still
breast-feeding. Rich women often employed wet-nurses to breast-
feed their babies. Babies seldom thrived, or even survived,
without out a regular supply of breast milk.