1839.] Description of an Astronomical Instrument. 831 



Art. V ' .—Description of an Astronomical Instrument presented by 

 Raja Ram Sing, of Khota, to the Government of India.— By J. J. 

 Middleton, Esq. of the Hindoo College, Calcutta. 



The instrument of which I am about to attempt a description, 

 was presented some time ago by the Raja of Khota to the Government 

 of India, as a very good specimen of its kind. The body of the 

 instrument consists of a square plate of pure and massive silver, in 

 addition to which, on one side, is a plummet or index-rod, which re- 

 volves freely in the vertical upon an axis fixed at one of the angles of 

 the plate, and at the termination of a tube of about one-sixth of an 

 inch in diameter, which runs the whole length of one side of the instru- 

 ment. On the other side an index, consisting of four hands, at right 

 angles to each other, and of nearly the radius of the plate, is screwed 

 on to the centre of the plate, around which it revolves at pleasure. 

 The drawings which accompany this description will render the above 

 observations quite clear. 



The Sanscrit inscription on the obverse of the plate, and occupying 

 a triangular space at one of its angles, informs us at once of the class of 

 instruments to which it belongs. The inscription may be rendered 

 as follows—" In the year 1891 Sumbut, (1756) " Shokabdha, in the 

 " month of Assar, on the 7th day of the moon, the son of Boidhanath, 

 " constructed this astronomical instrument, in accordance with the 

 " principles of an astronomical work, styled Jontro Chintamony, 

 " under the direction of Raja Ram Sing of Khota, (blessings be upon 

 " his head) who is an encourager of learned men." 



We learn from this, that the instrument is of very modern construc- 

 tion, a circumstance which however in no way detracts from its 

 substantial interest, since it is not indebted, so far as I can discover, 

 to modern principles of science, but might have been fabricated or 

 used by the Indian astronomer of some thousand years ago. This, 

 and the great rarity of astronomical instruments in India, at least 

 in this part of it, contribute to it considerable importance. Of 

 several learned Brahmins with whom I have consulted regarding 

 the instrument, no one could give any account of it; indeed, with 

 the exception of some unimportant facts, it was to them only a sub- 

 ject of astonishment ; some, it is true, had read of such instru- 

 ments in Bhascara, and other commentators on the Siddhants, but 

 their notions of them, thus derived, were in the highest degree 

 obscure. No additional fact is necessary to prove how rapidly Indian 



