[ 19 ] the requisite instruments. The old Siddhantas give brief in- structions for constructing them, and he had no other alternative than to make for himself, & few primitive instruments fur measuring time and angular distance. Some of my readers may be desirous of knowing something of his observatory. It was the clear, blue vault of the heavens that was his observatory, and its equipment consisted of an armillary sphere and a vertical wheel as substitutes for modern transit and alta-azimuth, and the time-honoured clepsydra took the place of the sidereal clock. Of course, the all-useful gnomon found a place in the observatory, and I am informed, he had also a self-revolving instrument ( 1 ) made of the pericarps of the Bottle-Gourd (Lagenaria Vulgaris) with water and mercury. But it was more of the nature of a curiosity than of much practical use. The instrument, of which he inade con stant use, was one devised by himself. This, which he is fond of calling his Mánayantra (measuring instrument), may be properly called a tangent-staff. It consists of a thin rod of wood, twenty. four digits long, at one end of which is fixed another rod at right angles in the form of a T. The cross-piece is notched and also pierced with holes at distances equal to the tangents of the angles formed at the free extremity of the other rod. Of course, such & rude instrument did not admit of being 80 divided as to enable him to measure a degree with any accuracy. But it is a real pleasure to see him handling his Mánayantra, with a precision marvellous to behold. Constant practice has given him such facility with it, that he would not care to have recourse to his other instruments, although better suited for Digitized by Google
