308 HINDOO MATHEMATICS. 



of a pretension to antiquity which outrages all probability j 

 yet this is not any part of the doctrines themselves : set- 

 ting aside what is fabulous, there yet remains sufficient to 

 give the subject high interest as a most important feature in 

 the history of the pure mathematics. 



In the Surya Suldhanta, notwithstanding the mass of 

 fable and absurdity which it contains, there is a very ra- 

 tional system of trigonometry. This has been made the 

 subject of a memoir by the late Professor Playfair, in the 

 fourth volume of the Edinburgh Philosophical Transac- 

 tions ; and although it be evidently written with a belief of 

 the truth of Bailly's visionary system deeply impressed on 

 his mind, yet, leaving out of view the question of absolute 

 antiquity, it will be read with all the interest which that ele- 

 gant writer has never failed to excite, even when the reader 

 is not disposed to agree with him in opinion. 



We have already noticed that the Indians divided the cir- 

 cumference of a circle into 360 equal parts, each of which 

 was again subdivided into sixty, and so on. The same di- 

 \ision was followed by the Greek mathematicians. This 

 coincidence is remarkable, because it has no dependence on 

 the nature of the circle, and is a matter purely conventional. 

 It is probable both nations took the number 360 as the sup- 

 posed number of days in a solar year, which might be the 

 first approximation of the early astronomers to its true 

 value. The Chinese divide the circle into 365 parts and one- 

 fourth, which can have no other origin than the sun's an- 

 nual motion. 



The next thing to be mentioned is also a matter of arbi- 

 trary arrangement, but one in which the Bramins follow a 

 mode peculiar to themselves. They express the radius of 

 a circle in parts of the circumference. In this they are 

 quite singular. Ptolemy and the Greek mathematicians 

 supposed the radius to be divided into sixty equal parts, 

 without seeking in this division to express any relation be- 

 tween the radius and the circumference. The Hindoo mathe- 

 maticians have but one measure and one unit for both, 

 xdz. a minute of a degree, or one of those parts of which the 

 circumference contains 21,600, and they reckon that the 

 radius contains 3438. This is as great a degree of accuracy 

 as can be obtained without taking in smaller divisions than 

 minutes, or sixtieths of a degree. It is true to the nearest 



