268 



Scientific Intelligence. [no. 2, new series^ 



night ; the highest nightly rise being at 10 p. m. and the lowest 

 descent at 157a. or 3 a. m. : the daily range being on an average 

 0120, and that during the night about half as much. The varia- 

 tions in the times or range between the different months is very 

 trifling, but the mean value for each month shows considerable alter- 

 ations; the mercury standing highest on the average in January, 

 falling gradually until June, and rising again from July to Decem- 

 ber, the jise being usually, but not always, most rapid from October 

 to November. The same general course is also visible, though sub- 

 ject to great fluctuation, in the curve of daily means at the foot of 

 each Barometer Plate, where are shown the successive changes in 

 the mean height of the mercury from day to day. In most of the 

 years there will be seen one or more considerable depressions about 

 the beginning of November, indicating the effect of the storms which 

 so frequently occur about that time. 



The Thermometer curves have rather a peculiar form ; that por- 

 tion which belongs to the day, viz. from ISh. to Qh., having nearly 

 a parabolic shape, while the night portion scarcely differs from a 

 straight line, showing a nearly uniform descent from sunset to sunrise > 

 the change from the night to the day being much more abrupt than 

 the converse. The coldest time of the 24 hours appears to precede 

 that of sunrise by a few minutes ; the hottest time is about 1^. 10m. 

 p. m. , but varies in the different months from Oh. 30m. to 2h. June 

 is on the whole the hottest month but is nearly equalled and in one 

 year surpassed by May. The coldest month is January, but De- 

 cember and February differ but little from it. The range of tem- 

 perature is seen to be much greater in the hot than in the cold 

 season, the least occurring in November. The mean daily range 

 amounts to 12?. 



New species of Silk Worm. 



" The Agri-Horticultural Society op India has reported 

 most favourably on a new variety of silk, brought into notice by 

 Capt. Hutton, of the invalids, a resident of Landour. The worm 

 which produces it (Bomhyx Huttoni) spins in all weathers, whereas 

 the common silk-worm is apt to be thrown off work by a passing 



