280 



METEOEOLOGY AND ALLIED SUBJECTS. 



Dr. Augustin has published an elaborate study upon the self-recorded 

 temperatures at Prague during the interval 1840 to 1877. Tlie MIott 

 ing extract shows the direct influence of iusolfttion and of cloudiness : 



Month. 



Deo 



Jan 



Feb 



Mar . . . . 

 Apr . . . . 



May 



Juno 



July 



Aug . . . . 

 Sept.... 



Oct 



Nov . . . . 

 Year 



846 wholly clear days. 



02 



— 5.7 



— 8.5 



— 5.4 

 + 2.7 



9.4 



15.8 



19.6 



22.0 



21.5 



16.6 



9.2 



0.0 



8.1 



^■S 



5.2 

 5.6 

 7.2 

 9.5 

 12.5 

 12.3 

 11.5 

 11.9 

 12.2 

 12.0 

 10.8 

 5.9 

 0.5 



II 



h.m. 

 7 10 a. m. 

 7 20 

 7 20 

 6 10 

 C 

 5 50 

 5 

 5 30 



5 50 



6 10 



6 25 



7 10 

 C 25 



-=> a 



h.m. 



2 30 p. m. 

 2 40 

 2 50 



2 57 



3 15 

 3 9 

 3 15 

 3 35 

 3 20 

 3 5 

 2 40 

 2 30 

 2 59 



2, 279 cloudy days. 



a 2 



+ 0.3 



— 1.1 



+ 0. c 



3.2 



7.5 



11.9 



15.0 



10. 5 



10.9 



13. 2 



8.9 



3.5 



8.0 



1.2 

 1.4 



2.3 

 3.0 

 4.0 

 4.1 

 4.0 

 4.4 

 3.7 

 3.7 

 3.1 

 1.9 

 3.1 



•f a 



h. m. 

 7 a.m. 

 6 30 

 6 5 

 6 5 

 5 50 

 5 40 

 4 40 



4 50 



5 40 



6 

 5 50 

 23 

 5 53 



h. m. 

 2 p. m. 

 2 

 2 15 

 2 15 

 2 20 

 2 40 

 2 30 

 2 50 

 2 40 

 2 30 

 2 10 

 2 30 

 2 23 



{Z. 0. G. M., XVI, 1881, p. 168.) 

 O. Jesse, of Steglitz, has investigated the diurnal variations of tem- 

 perature on clear days at Hamburg. His results are based upon the 

 records of the self-registering thermometer for three years at the Deutsch 

 Seewarte. He selected only very clear days and those on which the 

 temperature at the end of a twenty-four hour period agreed within one 

 degree centigrade of that of the beginning, hoping thereby to deduce a 

 simple relation between temperature and the altitude of the sun. The 

 months October, November, and December were too cloudy to afford 

 any proper data. His resulting equation gives the departure (w) for 

 any hour (x) from the mean temperature of any day of the year on which 

 the sun's altitude above the horizon at noon is Jt, and it reads as follows : 



^w={5o. 4 sin h) sin X— (lo.83) cos X 



* 4_ (00.70 sin h — 0.49 cos h) sin 2X. 



+ (10.28 sin h — 1.61 cos h) cos 2X. 



The departure of the computed from the observed values shows traces 

 of periodicity that are as yet unexplained. {Z. 0. G. M., 1881, XVI, 

 p. 96.) 



Billwiller, of Zurich, has studied the vertical distribution of tempera- 

 ture in the atmosphere within areas of high barometer and relatively 

 clear weather. He shows that the so-called anomaly, by reason of which 

 the air sometimes grows warmer as we ascend, or, more properly, th-e 

 layers of cold air lie quietly below the warm air, is due to terrestrial 

 radiation, and is a characteristic of areas of high pressure; also, that 

 this condition occurs in summer as well as winter, and tends to main- 

 tain the permanence of "high areas" in proportion to the increasing 

 length of the night-time relative to the day-time j also, that the areas 



