Apparently Sawai Jai Singh II (d. 1743), Raja of Amber and founder and Raja of Jaipur, had a keen interest in astronomy, because he commissioned the construction of six naked-eye observatories — jantar mantars – in his realm in the early 18th century. The one in Jaipur itself is a complex of structures hard to understand without explanation. Or even with explanation a lot of the time.
I didn’t take that picture, since that vantage was unavailable, or at least I didn’t know about it. Someone calling himself Knowledge Seeker thoughtfully released the image into the public domain, however. It gives a sense of the layout of instruments in a sort of plaza, though it doesn’t depict the large sundial, except right at the lower left corner. Just behind the Jantar Mantar is City Palace, more about which eventually, but which Jai Singh II also had built. One of those busy kings, sounds like.
“The Jantar Mantar observatory in Jaipur constitutes the most significant and best preserved set of fixed monumental instruments built in India in the first half of the 18th century; some of them are the largest ever built in their categories,” UNESCO says, for indeed it is a World Heritage Site, which are thick on the ground in India. “Designed for the observation of astronomical positions with the naked eye, they embody several architectural and instrumental innovations.”
This is the kind of place that reminds me once again how little I know. Such as about Indian astronomy, thousands of years in the making. A familiarity with that subject might help answer the question I have – why didn’t Jai Singh II incorporate places for telescopes? I feel certain he would have had some, imported or locally made.
The Jantar Mantar is also good for some gee-whiz moments, such as looking up at the world’s largest sundial.
Our affable guide in Jaipar that day, Ali, points to the time on the enormous dial plate. The instrument is capable of measuring time to an accuracy of two seconds (with some caveats; see “How accurate is it?” on this page).
He asserted that the sundial is indeed the world’s largest, though I’ve seen other sources that weasel with such phrasing as “one of.” I’ll go with Ali on this one: the largest in the world, unless I find out about a bigger one, and I’m not going to look very hard.
Ali also told us that his father was a tour guide in Jaipur, as was his father before him, which is some span, since he might have been close to my age. He was knowledgeable enough that being in the family biz seemed likely. He also might have had information about the use of telescopes back then, but I forgot to ask.
Other instruments, whose descriptions I read on English signs next to the Hindi, but which are less easy to understand than a sundial, except to say they are useful for tracking objects in the sky.
More structures, either built upward or downward.
Of course each instrument has a purpose and a name – such as Samrat Yantra, Jaya Prakasa, and Rama Yantra, which supposedly Jai Singh II designed himself. Detailed information is at jantarmantar.org. Even without a tight grip on all the details, there’s no doubt that the Jantar Mantar of Jaipur is impressive, besides having an impressive name that rolls right off your tongue.