Tag Archives: 2002 VERITAS

Women of Mathematics : Sophie Germain


Marie Curie worked hard for 10 years. She sacrificed her life for Science. In the end she was rewarded with a Nobel Prize.

  Have we not heard such tales of Scientists sacrificing pleasures of life and working real hard to contribute to Science. Such tales are written by historians and parents who want to “inspire” thier kids. These are all false stories. A Scientist loves science. They appreciate the beauty of the laws of nature. They want to spend their lives surrounded by this beauty. Science makes them happy.They do not sacrifice the pleasures of life. Science is their pleasure of life. So the true story would be ” Marie Curie enjoyed herself for 10 years finding why radioactivity happens. Everyday
was a new adventure. In the end she also got a lil medal called the Nobel Prize.”

       Today in VERITAS we will remember the story of Sophie Germain. You might think that it is a story of struggle and sacrifice. Try and read it from the correct angle: it is a story of love.


       Sophie Germain was born in 1776 in Paris.  When she was 13, Sophie read the story of Archimedes. She was surprised to read that Archimedes was so engrossed in doing mathematics that he ignored the soldier who threatened to kill him(and killed him). She thought that this subject must be really interesting. She started studying mathematics on her own and she loved it.

       Now in those days women were not supposed to study Science and Mathematics. Her parents discouraged her. They even went to the extent of taking away her clothes at night and depriving her of heat and light so that she would only sleep and not get up to do mathematics. She
could not study in the daytime because they would not let her. But she loved the subject and eventually her parents realized the futility of keeping her away from it. They let he do whatever she wanted.

       Women were not allowed to study in universities so she studied on her own. She borrowed lecture notes from Lagrange’s students to study. She assumed the male name of M. LeBlanc and even submitted a paper to Lagrange. Lagrange was impressed by the work and wanted to meet
his student. He was surprized when he realized that his student was actually a female and that she had been studying on her own. He advised
her on her work and encouraged her to do more.

       Sophie became interested in number thery and started corresponding with Gauss. She did not reveal her real name and corresponded as LeBlanc. They discussed mathematics for three years(1804 to 1807 ) before Sophie revealed her true identity. Gauss was thrilled to find that his
“pen-friend” was a very talented woman. She even saved Gauss’ life. In 1806 when Napoleon invaded Germany she contacted a french commander, who was a friend of her family and told him that Gauss should not be harmed. She remembered Arichmedes and did not want Gauss to have the same fate.

Sophie proved that if x,y and z are integers then if x^5+y^5=z^5 then x,y or z must be divisible by 5. Sophie’s proof was a major step in proving Fermat’s last theorem.

In 1808 the physicist Chladini conducted experiments on vibrating plates which exibited some strange figures called  Chaldini figures. The
Institut de France set a prize for anyone who could mathematically explain these figures.

       Sophie Germain started thinking about this problem. In 1811 her’s was the only entry trying to explain the figures. But her analysis was wrong( since she was not formally educated and did not have access to modern journals she had holes in her knowledge). She did more research. In 1813 she came up with a better explanation of the figures. This work was rejected too. In 1815 however her third work on the subject got her the prize.

       Most Scientists and Mathematicians however chose to ignore her and her work.  Sophie was not discouraged by this and kept working on mathematics till her death in 1831. Her death certificate did not list her as a Scientist or a Mathematician, but a property holder.

      Sophie did not have any formal education.  Despite that she made great contributions to number theory, theory of elasticity, theory of vibrations etc.

       Most of us lay too much stress on degrees acquired in colleges and universities. Are these degrees really important? Isnt having a “fire within” more important. Isnt love the supreme conquerer?




 Go, wondrous creature! mount where Science guides:
 Go, measure earth, weigh air, and state the tides:
 Instruct the planets in what orbs to run,
 Correct old time and regulate the Sun;

Creative Commons License
Veritas by Kanwarpreet Grewal is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License.

Mysteries of the Brain : Part – 5


The last VERITAS was on the mysteries of the brain and I would have liked to wait for sometime before sending something on the same subject. But what I saw on TV last week was so interesting that I could not wait.

People say that blind people develop other senses to help them overcome their handicap. Is this really true? Are our brains changable? or are their functions fixed at birth ?
A very interesting experiment was conducted by Dr Alvaro Leone to see if brain functions can change to suite the individual. A patient was blindfolded for a period of 100 hours and made to learn braille for several hours a day. So the patient could not see anything for a period of hundred hours and had to just learn to “read” braille.As you all know Braille script is made of dotted patterns and a blind person can feel the shape of the patterns and thus read the “text”.
Now we must understand that the brain area for touch (and therefore responsible for “reading” braille) and visual recognition are different. The visual cortex is responsible for interpreting what we see. The brain area for touch is the parietal lobe. The visual cortex is located near the back of the brain. The touch area is in the middle part of the brain.
       In the first 2-3 days of “blindness” the patient’s ability to “read” braille was very limited. She learned very slowly. But in the last 1-2 days her progress became really fast. The scientists used electrodes to see which parts of the brain were active at this time. They were surprised to find that the visual cortex was equally active alongwith the parietal lobe when the patient was reading braille.
It is as if the visual cortex realized that the person can no longer see and that it has nothing to do. The visual cortex changed its role and started helping the area responsible for the sense of touch.
So in blind people the visual cortex tries to help cope with the handicap by helping the other parts of the brain responsible for the other senses. That is how blind people develop other senses more than people. A handicap in one sense would develop the other senses more. The physical handicap does not waste the brain part responsible for it. The brain part changes its role to further develop the other senses.

        The wonderful thing is that it just took about 5 days for the brain to change! Think about this….

  At the end of the 100 hours the blindfold was removed and the patient could see again. After a few hours the patient’s visual cortex returned to its real role: visual recognition. The patient’s ability to read braille again decreased. The visual cortex no longer helped the sense of touch.
Isnt this wonderful! We see that our brain is a very efficient organ. It tries to adapt to help the individual as much as it can. Most of us realize that excercising the body is important. But excercising the mind is important too. If you just use your mind on one activity then you should know that the areas responsible for other activities would adapt and change. You should restart doing some maths again or soon you would be
mathematically challenged! Enjoy your brains… there is a whole kingdom in there:
                     My mind to me a kingdom is,
                     Such present joys therein I find,
                     That it excels all other bliss
                     That earth affords or grows by kind:
                     Though much I want which most would have,
                     Yet still my mind forbids to crave.
( The TV program that inspired this VERITAS was “Changing your mind” which appeared as a part of the National Geographic series Scifiles.
The poem that appears at the end of this VERITAS is a part of the poem “My Mind to Me a Kingdom Is” by Sir Edward Dyer)


  Go, wondrous creature! mount where Science guides:                 
  Go, measure earth, weigh air, and state the tides:                 
  Instruct the planets in what orbs to run,                          
  Correct old time and regulate the Sun;                             

Mysteries of the Brain Part – 4




Friends, we have all heard the old saying ” a healthy mind in a healthy body”. Is this really true? Does our mental health affect our physical health? What is the relationship between the brain and the body… the nervous system and the immune system? Today in VERITAS,we explore this relationship.

There are two response systems in our bodies: the Brain’s stress response system and the immune system. The stress response system creates/controls stress resulting from stimulus which occurs both within and outside the body. The immune system kills any external organisms and protects us from disease.
The internal steady state of a body is called homeostasis. This is the state of internal well being. The stress response system and the immune system try to maintain this state. The immune system and the nervous system communicate with each other. One hormone shared by the nervous system and the immune system is the corticotropin-releasing harmone(CRH). This hormone is produced in the brain. When released
the CRH causes the pituitary to release cortisol, the best known stress harmone. Now you must remember that the immune system is an
extremely lethal system and must be controlled. If it is not controlled it can go against the body it protects. The stress harmone cortisol controls the immune system. Also cortisol prevents the release of more CRH by the brain and thus regulates the immune system as well as the stress levels.

Another important link between the nervous system and the immune system are the cytokines. The cytokines are protein molecules that send signals from the body’s immune system to the brain. This communication may be by directly going to the brain or by interacting with nerves as far away as the heart. A typical communication takes milliseconds. Activation of the brain by the cyclokines activates different stress responses
in the brain. The response is aimed at staying away from trouble as long as the body is ill. This is the reason why illness causes us to feel over sleepy or lazy. The body wants to get better before fighting again. The immune system tells the brain that the body is ill and should take care.

Of course what I have outlined above is just a small part of the vast communication that exists between the brain and the immune system. But what is clear is that stress and immunity are related. Stress is the brain’s way of controlling/reducing the effects of the immune system. The immune system and the stress response system control each other from overreacting to things.

So what happens when you get stressed because of work/society? The brain does not know if this stress is caused by illness or by something else. Short term stress is okay but if you are stressed about something for a long term then the brain thinks ” this guy is ill. I am sure the Immune system is going overboard… so lemme control it”. It sends CRH and reduces the immune system. So your immunity is lowered
even though you were stressed because of your “cranky” boss. And you get ill. So stress reduces the immunity of the body.

However very high levels of stress can sometimes increase the immune system for a short time. For example during exams students do not generally fall ill. But soon after exams when the pressure is off the illness occurs. However we must remember that different bodies have different stress thresholds and may react differently. There are several illnesses that can be caused by the break of interaction between the immune system and the nervous system. To give you an example : melancholia is a disease in which the immune system has forgotten to switch off the brain’s stress response system…. the result?
Very little sleep, not a good sense of humour, an over stressed individual.

Take another example: depression is the result of hyperactive immune system. The stress response of the brain is lessened. The person sleeps too much, eats too much and gains weight. studies have shown that people with prolonged stress are more likely to have common cold.

Interesting fact: About 20 % of patients with arthritis show clinical depression. You would think that the depression is because of their severe pain in the joints. But that is not the case! Sometimes the pain in the joints does not coincide with the depression symptoms. The reason for this is this: a disturbance in the body’s internal well being may sometimes manifest in the physical disorder(pain in joints) and sometimes in the mental disorder(depression) and sometimes in both. So if you have to remain healthy you have to take care of both your brain and your immune system.
So any problem inside the body may manifest itself as a physical disease or a mental disease.

Today there is a lot of research going on to see if medicines for the nervous system can be used to cure diseases of the body and if antibiotics can be used to cure mental disorders by influencing the immune system.


( The information for this VERITAS has been taken
mainly from the Scientific American article ” The mind
body interaction in disease
” by Sternberg and Gold. Thanks
to Sakharwade for sharing this article with me.


  Go, wondrous creature! mount where Science guides:
 Go, measure earth, weigh air, and state the tides:
 Instruct the planets in what orbs to run,
 Correct old time and regulate the Sun;


The Crab Nebula



In  July 1054 a strange and very large star mysteriously appeared in the sky. The new star was so bright that it could be seen even during the day time. The Chinese astronomers were very excited and maintained an exact record of the star’s dramatic appearance and its eventual disappearance from the sky. The Red Indians were so inspired by the new star that they drew pictures of it in their caves. However no records of
this event have been kept by Indians or the Europeans. Our ancestors may not have seen it because all this happened in the monsoon months of July and August. The Europeans may have chosen to ignore it because it would have gone against their belief that the universe created by God is perfect and the heavens do not change.

       This was a most astonishing event. New stars dont just appear! According to the Chineese the new star gave out intense rays even during the day time and it had a reddish white colour. The star remained visible at evening time for almost a year and then it faded away just as mysteriously as it had arrived.

       This mystery was forgotten for almost 600 years. The invention of the telescope helped astronomers look closely at the site where the mysterious star had appeared. In 1731 the English astronomer Charles Messier observed strings of gas and dust at exactly the same position in the sky. They called it the Crab Nebula( A cloud that looks like a crab). This was the first intergalactic cloud(nebula) to be observed. Astronomers
were fascinated by this strange object and started sudying it with their telescopes.

         In 1939 John Duncan calculated that the crab was expanding and would have have started as a point object about 800 years earlier. A few years later scientists armed with even bigger telescopes observed a much smaller star at the center of the Crab nebula. This star was emitting the most powerful radio waves compared to any other celestial body.

       Today we know that the bright “new” “star” that appeared mysteriously in July 1054 was actually the death of a star. A star almost 50 times larger than our Sun had exploded. This phenomenon is called a Supernova( nova means new). All the mass that this star contained became clouds of dust ( the nebula). And the core of the star turned into a neutron star( a star having no electrons…just neutrons). It emits powerful radio waves. So what happened in the year 1054 was a cataclysmic explosion.

       The explosion took place almost 6500 light years from the earth. So if it was visible during daytime on earth you can imagine its power. If it had happened even as far as 50 light years from earth life on earth would have been destroyed because of the intensity of the radiation

       Everything in the universe is very far from us. Light takes 6500 years from the crab nebula site to reach the earth. So the actal explosion started in the year 5446 BC. The filaments of the nebula are still expanding at the rate of 1000 Kms per second. The diameter of the crab nebula is 6 light years! The pulsar (the small neutron star at the centre) is about 12 Kms across and rotates about its axis at 33 times per sec.

       When we fight with each other we do not realize that the earth is just a small insignificant dust particle in the universe. The universe outside is MUCH MUCH bigger and so many more exciting things happening. There is so much going on…. How can we fight with earh other over insignificant things????

       When everybody is making a face
       and calling each other names
       And the whole world is ajangle and ajar….
       I meditate on interstellar space
       And smoke a mild cigar…. 😉


( References: Todays VERITAS has been inspired by the book “Violent Phenomenon in the UNiverse” by Jayant Narlikar. The little poem at the end has been taken from the poem Canopus written by Bert Leston Taylor. )


 Go, wondrous creature! mount where Science guides:
 Go, measure earth, weigh air, and state the tides:
 Instruct the planets in what orbs to run,
 Correct old time and regulate the Sun;

Creative Commons License
Veritas by Kanwarpreet Grewal is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License.

Mysteries of the Brain Part – 3


He who would study organic existence ,
       first drives out the soul with sheer persistence ,
       then the parts in his hands he may hold and class
       but the link with the soul is lost alas

       Today’s VERITAS is inspired by an article from the Scientific American which Sakharwade gave me to read. There is very little I know about this topic… there is very little that anybody knows about this topic. I wanted to post this as a part of “MYSTERIES OF THE BRAIN” series because this IS the ultimate Mystery of the Brain.

       The brain is a collection of cells that communicate with each other, perform some brain operations(storing data, telling the body what to do etc). Is that all? No! There is a basic thing missing from the above picture: consciousness…. being aware, to feel, the concept of self. Why am I sitting and writing this VERITAS mail?
I have a purpose. A picture of self that would not be complete if I do not do this. This is consciousness. The separation of self from the external world. We can create machines that process data, store information but are still so incomplete! They do not have a sense of I.

      How does this feeling of consciousness emerge from the collection of cells that we call the brain? A lot of research is being done to find an answer to this question. But this is not easy. The author of the Scientific American article  Antonio Damasio says: “But declaring defeat even before we make the attempt defies Aristotle’s observation that human beings are infinitely curious about their own self”. Well said!

Go wonderous creature, mount
where Science guides…

   Demasio’s proposal is break up the consciouness problem into two parts:

a) The “movie-in-the-brain” b) The “self”.
The “movie-in-the-brain” is the sum total of all the sensory experiences we have: the sights+ the sounds + the smells + all that we experience. The self refers to the sense of ownership we give to the “movie-in-the-brain”. This is what I see, this is happening to me etc.

 Solving the “movie-in-the-brain” part is easier and much has been achieved. The work of mapping different areas of the brain to different functions began over 150 years ago when Broca and Wernickle suggested that different parts of the brain are involved in different aspects of language processing. We have achieved a lot in this area. Scientists can today study the activity of a single neuron and relate the activity of the area it is in to a specific mental state. For example scientists have been able to figure out what brain circuits are involved in the recognition of different shapes. Edges oriented in different angles trigger off different neurons… Wow!

  But solving the “self” part of the problem is more difficult . Demasio has a theory that I will now explain. The main idea is that the cells in the brain are unique because they are about other parts of the body. Cells in any organ of the body (liver, kidney) etc just work to perform their own organ roles(that of liver or kidney etc). However the cells in the brain are , at every level of the nervous system, supposed to represent other organs or events occurring to other organs. For each part of the body there is a corresponding mapping in the brain. Demasio says “Evolution has crafted a brain that is in the business of directly representing the organism and indirectly representing whatever the organism interacts with”.

  The brain is also responsible for maintaining the internal chemical and electrical balances. So EVERYTHING that happens withing the body is mapped in the brain. But most of the work done by the brain is automated. The brain does not want to disturb the body with the mechanics of the internal process management. The brain just wants the body to take care when it faces an external stimulus. So it creates a second order
representation of the outside world in which the body’s sole aim is self preservation. So the self is a second order representation of what we must do when we are in the midst of the external stimulus: we must think about ourselves… we must be conscious… we must be aware. The part of
the brain that controls our intelligence is just given a picture of the “self” and that the “self” is the most important thing. So all our intelligence puts the self at the core of our “movie-in-the-brain”. Only the self aware organism has the ability to react to alarm signals from the “movie-in-the-brain”. Evolution demands consciousness!

  Have we explained the mind? the soul? No! we have just started. Would you like to participate in this quest?
A quest that may last a lifetime… but what a lifetime it would be! Or are you just happy playing with the silly little toys that you have “invented”??!! And you call such childish games creativity??? 🙂 . There was only one moment of Creativity. We humans can just draw His lines after Him.



 Go, wondrous creature! mount where Science guides:
 Go, measure earth, weigh air, and state the tides:
 Instruct the planets in what orbs to run,
 Correct old time and regulate the Sun;

Mysteries of the Brain Part : 2


This article was written on 2 July, 2002 
        I would like to thank Sakharwade for making me read some very interesting articles on the Brain published in a special edition of the Scientific American. Today’s VERITAS is inspired by one of these articles.

Have you ever wondered if your emotions are permanent or temporary?
If you are afraid of something would you fear that thing for a long time or would you be able to control it? Why do emotions always hit you before reason does? Where are the emotions stored in the brain?

The emotional aspects of the brain have been studied for about a decade now and Scientists have some up with some pretty interesting facts.
The brain pathway of one emotion has been studied in detail: fear.

 Joseph LeDoux and his team did some very interesting experiments on rats called fear conditioning. A set of rats were made to hear a sound and
the sound was followed by a mild electric shock on the base of the cage. 
After 2-3 sound-shock pairs the rats began to associate the particular sound with shock. And later even if the shock was not given the mice
would still show fear(high blood pressure, freezing) on hearing the sound. The Le Doux and his team made lesions on various parts of the rat’s brain to study where emotions are stored and how they can be removed.

There are four parts that interests us : thalamus, Amygdala , Cortex and the Hippocampus. The purpose of these various parts is :

1)Thalamus: The stimulus(from the outside brain enters from here). It sends these signals to various other parts for processing.

2) Amygdala: This is an almond shaped part deep in the brain. It stores emotional memories. In our rats it stores “sound means shock so RUN!!”
kind of simple associations. It activates emotional response(high BP,fight , run , heartbeat etc)

3) Cortex:  The part involved in planning and thinking.

4) Hippocampus: This stores declarative memories(facts). The emotional part of the memories is not here.

The basic pathways of emotions are these:

outside stimulus  -> thalamus -> amygdala     ..1

outside stimulus  -> thalamus -> cortex -> amygdala     ..2

outside stimulus  -> thalamus -> cortex -> Hippocampus -> amygdala  ..3

  So this is what happens when you see something: Lets say you see a wooden stick that resembles a snake. The message from the eyes
reaches the amygdala from 2 different paths: from the thalamus directly(pathway 1) and from the thalymus->cortex(pathway 2).
But pathway 1 is faster because it has one link less. Pathway 2 involves the cortex and involves thought. So when you see
the stick the first thing that happens is that the amygdala forms the association “Snake so RUN!”. But after a short time
the cortex (having examined the object and having thought) sends a message to the amygdala : “Dont bother… it is a stick”
So Emotions always hit you before thought does. Our evolution has made us this way. You would be better off confusing a
stick for a snake than examining everything before deciding to act. SUrvival is the primary need.

   AFter this the scientists started giving the rats the sound but not following the sound with a shock. Slowly the response of the rats started diminishing. They realized that sound is not followed by shock. So their emotions to the sound decreased. Now the team removed the cortex of these mice. Then they delivered the sound to the mice again and the mice showed the old HIGH level of fear! The scientists realized something:
the emotional associations that form in the amygdala are PERMANENT! You cannot change your emotions! The cortex merely changes your
response to your emotions. So if you like or dislike something you will do that all your life. However your response to it may change because of conscious thinking.

     Now something interesting: the Hippocamus stores factual memory. For every emotion stored in the amygdala there is a set of facts stored in the Hippocamus. When you see something both these memories are retreived together. For example if you had an accident a long time back you would remember how you felt and also remember the facts about how it happened and what happened after that. Each of these memories can trigger off the other.

   When we are children our Hippocamus is not developed. But our amygdala is. So if you go through a disturbing experience during
childhood you may develop a lifelong emotion(fear maybe) towards it without remembering the actual incident!

    The scientists found that people with irrational fears can never be completely cured. A person who has been treated for a phobia can go back to his initial state if he goes through an emotionally disturbing experience. The fear association in the amygdala is permament. The cortex may behave differently but you cannot change the amygdala.

    The brain is a complex and wonderful thing. The more we study it the more we are surprized at ourselves. When I got to understand the permanent nature of emotions I, in a way understood myself. I feel less responsible now for being me…


  Go, wondrous creature! mount where Science guides:                 
  Go, measure earth, weigh air, and state the tides:                 
  Instruct the planets in what orbs to run,                          
  Correct old time and regulate the Sun;                             

Mysteries of the Brain : Part 1


        Today we begin a series of VERITAS on the mysteries of the human brain. This series would span several months and you will see several VERITAS on other topics in this time too.
Today’s VERITAS is inspired by the book “The Dragons of Eden” written by Carl Sagan.
  Have you ever got this feeling that you recognise a face but you cannot describe it in words. Or you can recall the words in a song only by singing it. Do you know that people who stammer never stammer while singing ?

        Our brain has 2 hemispheres. The right and the left and they have different responsibilities: The right is responsible for pattern recognition, geometrical capabilities, musical abilities this is the intutive side of the brain. The left is the logical, rational side and is responsible for language( in 90% of the population) , math etc. Our right side of the body is connected to the left brain hemisphere and the left side is connected to the right hemisphere. So the left ear is connected to the right side etc. The eye however is different … each eye sees the world in two parts: the left visual field and the right visual field and they are connected to opposite hemispheres. All this is common knowledge. The mystery begins now.

 There is a bundle of nerves that connects the right and the left hemispheres. It is called the corpus callosum. It helps the communication between the two hemispheres of the brain.
 Epilepsy is caused when an electric storm starts in one hemisphere of the brain and travels to the other hemisphere … comes back to the
first and becomes self sustaining. A scientist named Sperry thought of an idea: Why not cut the corpus callosum ( connections between the
hemispheres) and then the epilepy causing electric storms would be contained. Sperry tried this in a set of patients having severe epilepsy
and the epileptic shocks ceased. Wonderful experiment. Cutting the corpus callosum SEEMED to cause no side effects in the patients.
 But then Sperry examined his patients in a deeper way and found something astounding. The lack of communication between the two hemispheres had some profound consequences:

    Such spilt brain patients talk about their feelings and emotions a lot less than normal. THis is because speech is located in the left hemi and the emotions in the right.
        Using some techniques Sperry showed the patients the word HAT BAND but he made sure that the right hemisphere could only see
the word HAT and the left hemisphere could only see BAND. After this the patient was asked to speak what he saw. The patients said BAND.
They could not say HAT. However the left hand could write the word HAT without problems.
 The patients were shown some geometrical objects and were asked to draw with both hands. The left hand could draw the pictures well ( the drawings were horrible but the main idea was correct). The right hand could not draw the basic picture right. It drew a sphere as a square.
  They also discovered that the logical left brain is paranoid about the future. It plans for the future all the time. The right brain is a happier person and just thinks about the present, It is more optimistic.
  Carl Sagan says that the left hemisphere(logical hemisphere) is constantly controlling the instinctive right hemisphere. However when we sleep and the left hemisphere is organising data collected during the day, the right hemisphere is free to do its wishful thinking in the form of dreams .
We dream about all sorts of things. But we cannot do any logical thinking in dreams and we cannot speak.
  Now when we dream there is always two of us… the main character in the dream and another smaller character who just watches the dream. This smaller character will sometimes tell you ” It is only a dream” . The main character is the right brain doing its wishful thinking and the left brain is the smaller watcher who would sometimes put its logic by telling you that ” it is a dream” .

Enjoy your brain(s)


  Go, wondrous creature! mount where Science guides:                 
  Go, measure earth, weigh air, and state the tides:                 
  Instruct the planets in what orbs to run,                          
  Correct old time and regulate the Sun;