Bharatiya Jyotihshastra (History of Indian Astronomy), translated by R. V. Vaidya v2.c12.s5.75

v2.c12.s5.75

HUNTER, visited four out of the five observatories about the year 1799 A. D. and wrote their description in the “Asiatic Researches” mentioned above. It is not given in full for want of space. The description of the observatory at Vāranasī, as given by Sherring (1868 A. D.) in his English book on the city of Vārānasī, is given here, the description* being based on an article by Paṇḍit Bāpūdeva on “Instruments located in the Māna Mandira”, (Other observatories are constructed on the same plan.):--This observatory is situated on the bank of the Ganges at a spot known as Māna Mandira† Ghat. It is known as ‘Māna Mandira’. This building and the whole locality is at present in the possession of the Mahārājā of Jaipur. The observatory building is quite firm and strong. After ascending the steps on the outside, one enters into the square. After crossing it through, one reaches a staircase which leads to the main part of the observatory. Some of the instruments in the observatory are very huge in size. This structure is likely to last for thousands for years very easily. Still, they are so delicate that they could give very accurate results as desired by the original constructor of these instruments. A Brāhmaṇa is appointed to look after its upkeep; but it has not been maintained by him in a good condition. The instruments are getting damaged on account of heat and rain; and their parts and subdivisions, being worn out, are vanishing away. After entering the observatory, one sees the ‘wall instrument’ (Bhitti Yantra). It is a wall 11 ft. high and 9 ft. 1½" long, built in south-to-north direction. With the help of this instrument, the altitudes and zenith distances of the noonday sun, its maximum declination and the latitude of the place can be found. There are two large circular structures near, one is made in stone and the other in mortar; and there is also a square structure made of stone. This might have been used for finding the shadow of the gnomon and the azimuth. But all the marks on them are now obliterated. There is a very big instrument known as Yantra Samrāt (the emperor of instruments). This is another wall 36 ft. long and 4½ ft. thick and build in the south-north direction. One end of the wall is 6 ft. 4½" high and the other is 22 ft. 3½" high; and this wall is gradually elevated towards the north so that the pole star is visible in the plane. With the help of this instrument, the meridian distance, declination and right ascension of celestial bodies can be found. There is another double wall instrument here. To its east is erected a Nāḍi Valaya instrument made of stone. There is similarly another small model of the Yantra Samrāt instrument. Near to it is a Cakra-Yantra fitted between two walls. It was used for finding the declinations of stars; but at present it is nor in good condition. There is a huge Digamśa instrument near it. It was used for finding the azimuths of stars. It consists of a pillar 4 ft. 2" high and 3 ft. 7½" wide. There is another concentric wall having double its height and build at a distance of 7 ft. 3½" from it. The top surfaces of both the walls are graduated in 360° and directions are noted on them; there is another Nāḍivalaya instrument to its south, but the marks on it are obliterated.