THE CONSTRUCTION TIMES OF SAWAI JAI SINGH’S OBSERVATORIES
By
Anand M. Sharan
Professor
Faculty of Engineering
E-Mail : asharan@engr.mun.ca
Date : March 2, 2006
ABSTRACT
In this work, the events of the declining years of Moghul Empire are studied. In these years, Sawai Jai Singh played a very important role, which is not very commonly understood by the scientific community. He kept his scientific interest alive even when he was fighting numerous battles, and built his solar observatories. Based on his observations, he published an accurate astronomical table called ‘ Zij-i- Muhammad Shahi ’. The actual construction times of these observatories are established from the historical study.
1. INTRODUCTION
There exists a lot
of confusion about the construction times of the five observatories built by
Sawai Jai Singh. The times range from 1719 to 17373. The most
common belief is that the
The author of this paper got interested in the life of Sawai Jay Singh because the author himself has worked in the field of solar energy and utilized this energy1,2. The instrument built for this purpose can be called as Surya - Mukhi Yantra ( Sun Facing Instrument ) where optimal ( minimal ) energy is needed to reliably track the sun based on the two motions ( spin and orbital ) of the earth. This instrument is an improvement over other photo – sensor based instruments.
The objective of this research is to show, based on historical facts available, that it was not the case. The actual truth is known from the study of Sawai Jay Singh’s life. From this study, one can wonder at the genius of Sawai Jai Singh as to how he could be so brave in battles that he had to fight in the most difficult times of the Indian History, and yet carry out his research interests unparallel in human history. No other scientist has achieved these goals.
2. LIFE OF SAWAI JAI SINGH
Sawai Jai Singh was born in the year 16884,5.
He did his early education at Benaras (
called
He succeeded his father to the throne in the year 1700 at age of 12 due to the
untimely death of his father. Aurangzeb was the ruler at
Prince Bidar Bakht was very pleased with Sawai Jai Singh and he was sent to
Khandesh with a promotion . In December 1704, Prince
Bidar Bakht, himself a governor, appointed Sawai
Jai Singh as the deputy governor of Malwa but the Emperor, Aurangzeb,
did not approve of this appointment5,6 He, Sawai Jai Singh
through his attorney, tried to make petitions for the deputy governorship
in the Court and finally succeeded in December 1705. We will see later that
Aurangzeb died in 1707 and the battle of succession began. Prince Muazzam, the
eldest prince, won this battle fought near
Table 1 shows various Moghul kings who ruled from
Sawai Jai Singh went to fight against Churaman Jat near
In the mean time, the rulers were changed three times in 1719 by Saiyid Brothers, and when, finally, Mohammad Shah became the ruler ( see Table 1 ) and he arranged for the murder of these two brothers after ascending to the throne. The second brother was murdered in 1722.
In August 1722, Sawai Jai Singh was appointed subahdar (
viceroy ) of
Only after the elimination of Saiyid Brothers, and defeating of the Jats, could Sawai Jai Singh breathe relief in
1722. In the next seven years from 1722 until
1729, Sawai Jai Singh spent his time in his own pursuits building his capital
at Jaipur, and many astronomical observatories at
After 1737 when he was relieved of his job at Malwa, he came back to his capital Jaipur, where he spent his remaining years of life until 1743, when he died.
3. THE CONSTRUCTION TIMES OF HIS OBSERVATORIES
The construction
times of these four (
The following are the paragraphs which are given in3 , and are from Zig-i- Muhammad Shahi ( this translation is based on Hunter ) :
PARAGRAPH 1
“He (Jai Singh) found that the calculation of the places of the stars as obtained from the tables in common use, such as the new tables of Saiyid Gurgăni and Khăqăni and the Tas ‘hilat-i Mulla Chand Akbar Shahi, and the Hindu books, and the European tables, in very many cases, give them widely different results than those determined by observation; [the problem was] especially [serious] with the appearance of the new moon—the computations of which did not agree with the observation. “
PARAGRAPH 2
“Realizing that important affairs, both regarding religion and the administration of empire, depend upon these; and that in the time of the rising and setting of the planets, and the seasons of eclipses of the sun and moon, many considerable disagreements, of a similar nature, were being found; he represented it to his majesty of dignity and power, the sun of the firmament of felicity and dominion, the splendor of the forehead of imperial magnificence, the unrivalled pearl of the sea of sovereignty, the comparably brightest star of the heaven of empire, whose standard is the Sun whose retinue the Moon; whose lance is Mars and his pen like Mercury; with attendants like Venus; whose threshold is the sky, whose signet is Jupiter; whose sentinel Saturn; the Emperor descended from a long race of kings; an Alexander in dignity; the shadow of God the victorious king Muhammad Shah, may he ever triumph in battle.”
PARAGRAPH 3
“He (Muhammad Shah) was pleased to reply, since you, who are learned in the mysteries of science and have a perfect knowledge of this matter, having assembled the astronomers and geometricians [of different schools of astronomy such as those] of the faith of Islam, the Brahmins and Pundits, astronomers from Europe, and having prepared all the apparatus of an observatory, do you so labor for the ascertaining of the point in question that the disagreement between the calculated times of those phenomena and the times in which they are observed to happen may be rectified. “
PARAGRAPH 4
“Although this was a mighty task, which during a long period of time none of the powerful rajas had prosecuted; nor among the tribes of Islam since the time of the martyr prince, Mirzä Ulugh Beg, whose sins are forgiven, to the present, which comprehends a period of more than three hundred years, had any one of the kings possessed of power and dignity, turned his attention to this object; yet to accomplish the exalted command received, he undertook the task with a great determination and constructed here (at Delhi) several of the instruments of an observatory, according to the books of the Islamic School of astronomy such as the ones erected at Samarkand.”
In order to remove these errors - new sets of observations were necessary. Thus, with the view of setting the astronomical tables straight, Sawai Jai Singh approached the then Moghul emperor Muhammad Shah with the request for permission to build these observatories.
A brief introduction about Ulugh Beg ( 1393 to 1449 ) 8 , the grand son of Timurlane , and who was assassinated by his son in 1449, is in order here because Sawai Jai Singh gave up the brass instruments in favor of large size brick and masonry instruments to achieve the needed accuracy where he could improve upon the existing tables.
Among the instruments specially constructed for the Ulugh Beg’s observatory was a quadrant so large that part of the ground had to be removed to allow it to fit in the observatory. There was also a marble sextant. Ulugh Beg's accurate tables of sines and tangents were correct to eight decimal places. Ulugh Beg's ‘ Catalogue of the stars’ , were the first comprehensive stellar catalogue since that of Ptolemy.
A very important question arises at this point in time –How could have the ruler complimented Sawai Jai Singh about his knowledge of astronomy, and how could Sawai Jai Singh in 1719 - promise the ruler to improve upon the existing tables made by Ulugh Beg using large brick structure at Samarkand in Uzbekistan ?
The author of this paper believes that the answer lies in the fact that Sawai
Jai Singh had already built his brick instrument at
Aryabhata (476 – 550 ) was the author of the first of
the later siddhantas ( principles ) called Aryabhatiya which sketches his
mathematical, planetary, and cosmic theories. This book is divided into four
chapters: (i) the astronomical constants and the sine table, (ii) mathematics
required for computations, (iii) division of time and rules for computing the
longitudes of planets using eccentrics and epicycles, (iv)
the armillary sphere, rules relating to problems of trigonometry and the
computation of eclipses. He lived at Kusumpur ( modern
Brahmagupta (598-668) was the head of the astronomical observatory at
Bhaskara (1114-1185) was the head of the astronomical observatory at
The center of astronomy was originally at Pataliputra in Magadh then moved to
The above two paragraphs on Brahmagupta, and Bhaskara show that
The author believes that it was the Samrat
Yantra ( see Fig. 1 ) built at
Another reason for this can be seen from Sharma’s book ( page
212, bottom paragraph ), where he writes – “ There are reasons to believe
that
Sawai Jai Singh left
Sawai Jai Singh came to
In other words, the observatories at
Jai Singh improved concept of time measurement over Ulugh Beg by building equatorial
gnomon which can measure time at a constant rate of the spin of the earth and
simpler than an ordinary sundial which is like the Sanku Yantra shown in Fig.
2. One can note that the tip of the shadow of the
bar is almost along the straight line in the east – west direction. This
is because
The whole idea of achieving better accuracy was to make observations from
several locations. In view of the above, one can correctly conclude that the
Ujjain observatory was built before 1717 when Sawai Jai Singh had spent
considerable number of years, and experimented with his masonry
instrument at Ujjain before undertaking the task in the Moghul Court of
correction of the existing tables of Ulugh Beg. This experimentation at
Secondly, as the quoted paragraphs from the ‘Zij-e-Muhammad-Shahi ‘ already point out that - In the year 1719, the ruler was very much impressed by the knowledge of Sawai Jai Singh.
Where is the evidence, without building any of the observatories, to show that indeed, Sawai Jai Singh had acquired the mastery in astronomy ?
As far as Malwa is concerned, he was again appointed subahdar in October, 1729 but this appointment lasted for 10 months only due to the interference of Muhammad Khan Bangash6. But, again, Sawai Jai Singh was made the subahdar in September, 1732 until August, 1737.
In all these observatories, a horizontal surface is essential. Before
constructing their masonry instruments, Jai Singh and his associates selected a
suitable ground first and leveled it with water standing in masonry channels
built just for this purpose. Such masonry channels may still be seen at Jaipur
and
The idea behind building a number of observatories at different locations in
the northern
4. CONCLUSIONS
Based on this study, the following statements can be concluded:
1. Sawai Jai
Singh’s astronomy was basically a Hindu Astronomy, and he was assisted by
Hindu astronomers at
2.
3. The
4. All the other
four observatories at
5. ‘Zij-e-Muhammad-Shahi ‘ was published after the observations made from all the five observatories.
5. REFERENCES
TABLE 1: A FEW MOGHUL RULERS OF
Number |
Ruler |
Years |
Comments About the Ascension to the Throne |
1 |
Aurangzeb |
1658-1707 |
|
2 |
Bahdurshah |
1707 - 1712 |
|
3 |
Jahandar Shah |
1712 - 1713 |
|
4 |
Farrukhsiyar |
1713 - 1719 |
Assisted By Saiyid Brothers |
5 |
Rafi-ul-Darajat |
1719 |
Assisted By Saiyid Brothers |
6 |
Rafi-ud-Daula |
1719 |
Assisted By Saiyid Brothers |
7 |
Muhammad Shah |
1719 - 1748 |
Assisted By Saiyid Brothers |