260 



GROWTH OP INDIAN CORN. 



of hot weather in the month of- June or early in July, 

 and a late fall with warm weather at the period of 

 ripening. It will not endure a mean temperature below 

 65° in the growing season, but the morning and even- 

 ing temperature may be low, provided the midday heat 

 is sufficient to carry up the mean of the month beyond 

 that point. This high curve of heat at midday is so 

 essential that, without it, there will be no formation 

 of saccharine matter in the plant, nor will it mature ; 

 while with it the temperature of the night may be 

 quite low. This is one, and almost the only, condition 

 absolutely essential to its successful culture, and this 

 condition is fulfilled in almost every part of the coun- 

 try, except the mountainous districts above mentioned. 

 As a means of reference, the following may be given as 

 the results of observations at the Observatory at Cam- 

 bridge during the growing months of 1854, 1855, and 

 1856, which do not vary much from the mean or 

 average temperature of these months in any series of 

 years. 



The observations were made four times a day, — at 

 sunrise, 9 a. m., 3 and 9 p. m., the latitude being 

 42° 22' 48", the longitude 71° 1'. 



The season of 1858 was remarkable in most parts of 

 New England as a season of frequent rains and cool 



