326 Meteorological Observations at Hudson, Ohio. 



their appearance whether snow is, or is not, falling at the time. 

 This variety I call stratus, under which term I iticlude all clouds 

 which cover the heavens with a nearly uniform and unbroken 

 sheet. It appears, then, that the stratus is the most common 

 cloud at all seasons of the year except summer, when the cu- 

 mulus prevails. This is more strikingly exhibited in the follow- 

 ing table, which is arranged by seasons. 



More than half the clouds of winter are stratus, and nearly 

 half those of summer are cumulus. The former, then, is with 

 propriety called the winter cloud, and the latter the summer 

 cloud. The cumulus is also more common at 3 P. M. than at 

 9 A. M., a natural effect of the sun's heat. 



The following table exhibits the average cloudiness of the dif- 

 ferent months according to three years' observations, represent- 

 ing a sky perfectly clear, 10 entirely overcast. For comparison 

 I have added the observations made at Dartmouth College by 

 Professor Young. 



