The lack of institutionalization of the scientific knowledge at the mass level was the main degenerating factor behind scientific and technological backwardness in the non-European countries including India, during the pre-modern period. Jai Singh had realized this fact, as he took initiative to establish the astronomical observatories known as Jantar Mantar at five different places, and further, tried to institutionalize the mathematical science- on the mass level in India ..
Jantar Mantar built by Sawai Jai Singh, the astronomer King, were one of the most important milestones in the history of Science in India. We should learn about achievements of our forefathers in other fields too not just military achievements.
One of the only two Asian Games held in India had Misra Yantra of Delhi Jantar Mantar as its logo.
Replica of Jantar Mantar built at Gunma Astronomical Observatory, in Takayama, Japan.
Replica of Samrat Yantra of Jantar mantar in Inter University Centre for Astronomy and Astrophysics at Pune.
Replicas of some instruments of Jantar Mantar in Maharshi Vedic Observatory, Iowa, USA.
Indian cosmology never ceases to amaze world, whether it's a matter of Hindu eclipse demons or the highly precise astronomical architecture
Jantar Mantar is a perfect place for those of us who loved Maths and Calculations at school. Standing at Jantar Mantar Jaipur makes you feel as if the small instruments of your geometry box have suddenly taken a giant avatar. The semi-circles remind you the D, the triangles remind you of their plastic versions and the markings on the instruments remind you of the scale. Some instruments remind you of the rotating globe.
Well you never know, our school geometry box may have been a miniature version of instruments at Jantar Mantar. After all, Jantar means Yantra or Instrument, and Mantra means Calculation – is that not what our geometry box helped us with?
What is Jantar Mantar?
Small or Laghu Samrat Yantra – Jantar Mantar at Jaipur
Jantar Mantar is Jaipur is one of 5 observatories made by Raja Sawai Jai Singh. The other observatories are in Delhi, Varanasi, Ujjain & Mathura. Jantar Mantar at Jaipur is the last one and hence probably the best one of the lot. Built in early 1728 CE, Jantar Mantar at Jaipur underwent renovation work at the turn of 20th CE. Records of this can still be seen on the walls including the names of the astrologers who validated the readings.
All the instruments are in stone, marble, and brass.
Jantar Mantar at Jaipur is located next to the city palace and just behind the famous Hawa Mahal. In fact, from anywhere in the premises of Jantar Mantar you can see the flag of Sawai Jai Singh still flying high. There is a full flag and there is a quarter flag – the latter indicates if the king is in residence.
Why Visit Jantar Mantar?
One of the few observatories that you can visit in India. It is like having a lesson in astronomy – first hand. It is to look at the world around the earth from a scientific perspective – may help you get poetic in the long run. Tells you where you are with respect to the rest of the universe.
It is simplest of the observatories to understand. You may be inspired to build one at home. Local astrologers still come here on the Purnima of Ashadh month at sunset time to predict the monsoons for the year.
Understanding Yantras of Jantar Mantar at Jaipur, A brief walk through the popular yantras at Jaipur’s Jantar Mantar:
Sawai Maharaja Jai Singh questioned the accuracy of European, Islamic and Hindu astronomical tables inaccurate, so he built several observatories to accurately measure the position of the sun, stars, moon and planets via naked eye sight and massive, precise construction.
Jantar Mantar - New Delhi
Geometric structures in red sandstone, shapes that had clarity, focus, and oozed science. Big, like an Athenian ruin.
How these massive structures had been built, by whom, or why. The best guess that would come to any mind was that it was a sci-fi set from the silent movie era, a cluster of dreamlike, cubist edifices, left behind by visionary filmmakers, The structures were more daunting as anyone got closer, with their strangely curved shapes, sweeping upwards, like skateboard ramps built for a race of giants. Or at least intellectual giants, we thought, once we understood that the complex had something to do with ancient astronomy. One of the structures had the shape of a Roman amphitheatre, and inside it was an intricate measurement system made of stone slats, for calculating something or the other.
The masonry instruments, which vary in size from a few feet to 90 feet in height, are Jai Singh's chief work.
- G.R. Kaye, The Astronomical Observatories of Jai Singh
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| we see represented in this 1808 aquatint by T & W Daniell. |
When Jai Singh designed the observatories, one of his foremost objectives was to create astronomical instruments that would be more accurate and permanent than the brass instruments in use at the time. His solution was to make them large, really large, and to make them of stone and masonry. This simple yet remarkable decision brought forth a collection of large scale structures for the measurement of celestial movement that is unequalled today. Among the many startling impressions for a visitor to one of the observatories, is the scale of the instruments. One is literally enveloped, and confronted with a space that is both aesthetic and mathematical. The time scale of the Samrat Yantra at Jaipur, for example, includes subdivisions as fine as two seconds, and as one watches, the motion of the gnomon’s shadow becomes a palpable experience of earth’s cosmic motion.
SAMRAT YANTRAS
Vrihat or the Big Samrat Yantra – Jantar Mantar – Jaipur
There are two Samrat Yantras – one small and one big. The small one you see as soon as you enter the Jantar Mantar. The big one is located at the diagonally opposite corner and is the largest instrument in the complex.
Both the instruments work on the same principle. A triangular wall is aligned with the axis of Jaipur – hence giving it a perfect North-South alignment. The shadow of this line when it falls on the semi-circular curves on the both sides, you see the local Jaipur time. The smaller or Laghu Samrat Yantra gives time to the accuracy of 20 seconds while the large one or Vrihat Samrat Yantra gives it with 2 seconds accuracy.
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| Plan of the Samrat Yantra at Delhi |
Some guides would tell you that the Laghu Samrat Yantra was a test model before constructing the larger one. Though a very small model of the Big or Vrihat Samrat Yantra can be seen at the Jantar Mantar.
On a clear sunny day, it is fascinating to see the shadow of sun move in a smooth motion at these instruments.
As Jantar Mantar deploys all three ancient coordinate systems of the five celestial coordinate systems known. In the image, the red (ecliptic) and blue (equatorial) coordinate systems are two of the three classical systems that feature in the monument's instruments.
Samrat Yantra is named after Pt Jaganath Samrat who helped Maharaja Sawai Jai Singh in studying astronomy. Another scholar involved was Pandit Keval Ram Ji. These scholars traveled to Greece, Arabia, Portugal & Britain to study astronomy along with studying the ancient Sanskrit texts including Vedangas.
DHRUV DARSHAK PATTIKA
Dhruv Darshika or North Pole View Yantra
This is the smallest and simplest of the yantras at Jantar Mantar in Jaipur. A slanting wall at an angle of 27 degrees points towards the North Pole. 27 degrees is the latitude of Jaipur – the location of the instrument. Basically, this tells you the North Direction – a basic static compass. Our hunch is that this may have been built first to set the direction for the rest of the observatory.
JAI PRAKASH YANTRA
Jai Prakash Yantra – Jantar Mantar Jaipur
This is the most intriguing yantra at Jantar Mantar in Jaipur. This is a set of two sunken half spheres in marble. They are non-identical twins cut out in white marble. Yes, that means they would literally complete each other if joined. Each cutting of marble marks an hour. This means every one hour the observer can stand in one of the spheres and take measurements.
The one whose shadow tells it all – Jai Prakash Yantra
The heart of this stunning instrument is a small piece of metal with a central hole hanging bang in the middle of the sphere. It is the shadow of this metal piece that tells gives all the answers that you seek from this instrument. List Of Instruments:
May well be Jai Singh’s most elaborate and complex instrument, See the time lapse video below to see how the Kappala Yantra tracks the sun’s movement.
Which make everyone say, that it is the most beautiful of all the yantras at Jantar Mantar. The spherical cut out balls in white marble against the red sandstone look fascinating. When the guide explains this – astronomy sounds simple and fascinating.
Kapali Yantra
These look like the prototype of Jai Prakash Yantra.
NARIVALAYA YANTRA
Narivalaya Yantra – Jantar Mantar at Jaipur
This intriguing instrument has two circular plates – one facing North and other South. The angle of these plates is such that they are parallel to the equator. A small nail-like rod at the center is this parallel to the earth’s axis. The shadow of this rod tells the time.
Sanskrit inscription on the Southern Plate of Narivalaya Yantra – Jaipur
The southern plate is sunlit from autumn to spring equinox and the northern one from spring to the autumn equinox. This essentially means that each of these plates is functional for 6 months of the year.
A Sanskrit inscription on the southern dial tells the story of conservation and renovation of this Narivalaya Yantra. It is very interesting, how first the Lord Ganesha is remembered, then the purpose of the instrument explained, then the curiosity of the ancestor who built it acknowledged before getting into the details of renovation. We wish ASI translates it for the visitors.
RAJ YANTRA
Raj Yantra with all Nakshatras mapped – Jantar Mantar at Jaipur
This is a large metal disc made of Ashtdhatu with the Nakshatras or constellations marked on it. Technically, it is called Astrolabe.
We had great fun at Raj Yantra. As soon as my eyes touched Raj Yantra – I read Rohini written in Devanagari script. I looked around and found some more names of Nakshatras written. Now, I am also named after a Nakshatra and hence began our search for my name on the Raj Yantra at Jantar Mantar. With a bit of help from Google, we found it almost at the top right of the disc. Believe me, I was on top of the world as soon as we found Anuradha written on Raj Yantra. Our guide, Dinesh ji, took us more seriously this point onwards and spent good 3 hours showing and explaining the rest of Jantar Mantar to us.
There are two hanging discs at Raj Yantra – one of them is a prototype potentially in iron and the second is the one I talk about above.
Raj Yantra is used once a month to work out the Indian Calendar.
RASIVALAYA YANTRA
Scorpio or Vrishchik part of Rasivalaya Yantra – Jantar Mantar at Jaipur
Rasivalaya Yantra is made of 12 yantras – one each for a zodiac sign. These measure the transition of the zodiac through the Meridien. Each instrument looks similar and has a resemblance to Samrat Yantra but each is mathematically different. This instrument is found only in the Jaipur Jantar Mantar.
On an ego trip, I just looked at the instrument of Scorpio in detail.
RAM YANTRA
Radial Rama Yantra at Jantar Mantar Jaipur
Ram Yantra is a lovely instrument. I remember Ram Yantra from Delhi Jantar Mantar where it is lovely in Red color.
Ram Yantra measures the altitude and azimuth of celestial objects.
Digamsa Yantra – This cylindrical yantra measures the azimuth of celestial objects.
Kranti Vritt Yantra – Used to measure latitude and longitude of celestial bodies.
Shashthansh Yantra
This is a 60 deg arch located next to the Vrihat Samrat Yantra. When you go inside the arch, sunlight enters the dark chamber through a hole and this is used to measure the distance from the sun.
Standing inside when you look at a small dot on the wall you bow your head in admiration for the architects of Jantar Mantar.
CHAKRA YANTRA
Chakra Yantra
The Chakra Yantra is a large metallic ring. I could not gather its purpose except that it is used to look at the sky.
Prototypes or Test Models of all Yantras
Kapali Yantra – potentially a prototype of Jai Prakash Yantra
For us, a fascinating part of Jantar Mantar was the prototypes of each instrument. They kind of tell you the experiments that went behind building these precise instruments. You can see smaller versions of each instrument. For metal instruments, you can see an experiment with various metals. These prototypes give you the feel of standing in a laboratory.
Each instrument has staircase for the observers to climb and take accurate readings. As a visitor, you are not allowed to climb any of the instruments.
It made me wonder if we should have indeed chosen a career in Physics, All big walls have arches below them – both to manage the weight of the wall and to add the contemporary aesthetics of the times. The place would be a bit boring without these arched windows.
Jantar Mantar at Jaipur is a fascinating place. All the instruments look so simple that you wish you could build them at home. But, as they say, it takes a lot of expertise to make the complicated look simple.
Geometry at play at Jantar Mantar – Jaipur
Jantar Mantar at Jaipur is a UNESCO World Heritage Site. It is open from sunrise to sunset – precisely the time yantras inside this complex work.
Ticket at the time of writing is Rs 50/- for Indian and Rs 200/- for Foreigners.
It is located bang in the middle of the Jaipur city, with access to everything that you can possibly require.
On an average people spend 45 mins to an hour at Jantar Mantar. I spent 3 hours and I think there are a few yantras I skipped. So, plan according to your interest in the sky and its mysteries.
If like me you are named after a Nakshatra – find out your name on Raj Yantra. Here is the list of Nakshatras for you.
Make sure the Sun is shining bright when you visit, to have the best experience.
It is a great place to take the children with you.
