532 KEPOBT — 1891. 



46. On the other hand all the comets ■which after perturbation are 

 moving in orbits somewbat but not greatly inclined to the ecliptic are 

 liable to meet, in fact are sooner or later almost certain to meet, other 

 planets in such a way as to suffer perturbations that will prevent future 

 close encounters with Jupiter. After such changes those comets must 

 be regarded as tolerably permanent members of the solar system. 



47. Comets that have motions not greatly inclined to Jupiter's motion 

 are, as figs. 2 and 4 show, more likely in subsequent passages near to 

 Jupiter to have their periodic times shortened than lengthened. On the 

 contrary those passing in nearly opposite direction to Jupiter's motion 

 will, as figs. 3, 5, and 7 show, be much more likely to have their periods 

 lengthened than shortened. 



All these causes combine and work together to the one end that those 

 comets which are changed by the perturbing action of Jupiter, or other 

 planets, from parabolic orbits of every possible inclination to the ecliptic 

 into short period ellipses, and become permanent members of the solar 

 system, will as a rule (but with exceptions) move in orbits of moderate 

 inclination to the ecliptic, and with direct motions. 



We know as a fact that most short period comets do move in orbits 

 having small inclinations and direct motions, while long period and para- 

 bolic comets move at all possible inclinations to the ecliptic. If the short 

 period comets have been changed by Jupiter and other planets from 

 parabolic orbits, the preceding investigation shows why their orbits have 

 now small inclinations to the ecliptic, and the comets themselves have 

 direct motions. 



The Recent Progress of Agriculture in India. By C. L. Tupper. 



[A Communication ordered by the Council to be printed in extenso among 

 the Reports.] 



Since 1884-5 the Revenue and Agricultural Department of the Govern- 

 ment of India has published very comprehensive returns of the agricul- 

 tural statistics of British India, showing from year to year the area irri- 

 gated by Government canals, the acreage under cereals and pulses, fibres, 

 and other crops, the total area cropped, and many other particulars. I 

 have abstracted some leading figui-es from these returns, and append my 

 abstracts to this paper. 



It will be observed that in the period of six years, from 1884-5 to 

 1889-90, comprised in these returns the total cultivated area has risen 

 from 126 million acres to 136 million acres. I give the increase in 

 round numbers, and I propose throughout the text of this paper to use 

 round numbers only, showing the most precise figures I can get, either 

 in footnotes or in the appended abstracts from the returns. The figures 

 of 1884-5 necessarily do not include Upper Burraah, nor do they include 

 Ajmere, or the pargana, or tract known as Manpur in Central India. 

 Accordingly, to arrive at the total increase of cultivation in the six years, 

 we must deduct for these localities some three million acres. We thus 

 arrive at an increase of seven million acres, or a little more than one 

 million acres a year. The population of India now amounts to 286 

 millions, of which 220^ millions live in British territory and 65^ millions 

 in the protected native states. In the decade 1881 to 1891 the increase 



