ASTRONOMY. 1 7 



different sides of the equator are either similar or 

 equal ; the true measurement has consequently given 

 a diversity of results. 



Mild Springs. 



The series of mild springs which ended about the 

 years 1785 or 1786, seems to have begun at least as 

 early as 1749, and to have lasted thirty-six years. 

 Our present series of cold springs has yet lasted only 

 twenty-three years, and of course we have thirteen 

 bad years to come. 



The Planet Tellus. 



The earth (Tellus) is one of eleven spherical bodies 

 denominated planets, which revolve round the sun, 

 its distance from which luminary being 93,595,000 

 English miles, and its mean diameter 7912 miles. It 

 completes its diurnal revolution in 24 hours, and its 

 annual revolution in 365 days, 5 hours, 48 minutes, 

 51". One satellite (the moon), 2180 miles in diame- 

 ter, revolves round the earth in 27 days, 7 hours, 

 and 43 minutes, at a mean distance of 237,000 miles. 



The Dog Days. 



From the heliacal rising of the dog-star (Sirius), 

 that is to say, its emersion from the sun's rays, which 

 now happens about the llth day of August, the an- 

 cients reckoned their dies caniculares or dog-days. 



Density of the Earth. 



The precession of the equinoxes, and the nutation 

 of the earth's axis, indicate, in the opinion of Laplace, 

 that the density of the earth increases towards the 

 centre. Mr. Cavendish, from some experiments 

 made with leaden balls, estimated the mean density 

 of the earth at 5.48 ; but the experiments at Schihal- 

 c 



